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KSH(1)									KSH(1)

NAME
       ksh,  rksh,  pfksh  - KornShell, a standard/restricted command and pro-
       gramming language

SYNOPSIS
       [ +-abcefhikmnoprstuvxBCDP ] [ -R file ] [ +-o option ] ... [ - ] [ arg
       ... ]
       rksh  [ +-abcefhikmnoprstuvxBCD ] [ -R file ] [ +-o option ] ...	 [ - ]
       [ arg ... ]

DESCRIPTION
       Ksh is a command and programming language that executes	commands  read
       from a terminal or a file.  Rksh is a restricted version of the command
       interpreter ksh; it is used to set up login names and  execution	 envi-
       ronments whose capabilities are more controlled than those of the stan-
       dard shell.  Rpfksh is a profile shell version of  the  command	inter-
       preter ksh; it is used to to execute commands with the attributes spec-
       ified by the user's profiles (see pfexec(1)).  See Invocation below for
       the meaning of arguments to the shell.

   Definitions.
       A metacharacter is one of the following characters:

	      ;	  &   (	  )   |	  <   >	  new-line   space   tab

       A  blank	 is a tab or a space.  An identifier is a sequence of letters,
       digits, or underscores starting with a letter or	 underscore.   Identi-
       fiers  are used as components of variable names.	 A vname is a sequence
       of one or more identifiers separated by a . and optionally preceded  by
       a  ..   Vnames  are  used  as function and variable names.  A word is a
       sequence of characters from the character set defined  by  the  current
       locale, excluding non-quoted metacharacters.

       A  command  is a sequence of characters in the syntax of the shell lan-
       guage.  The shell reads each command and carries out the desired action
       either  directly or by invoking separate utilities.  A built-in command
       is a command that is carried out by the shell itself without creating a
       separate	 process.   Some  commands are built-in purely for convenience
       and are not documented here.  Built-ins that cause side effects in  the
       shell environment and built-ins that are found before performing a path
       search (see Execution below) are documented here.  For historical  rea-
       sons,  some  of these built-ins behave differently than other built-ins
       and are called special built-ins.

   Commands.
       A simple-command is  a  list  of	 variable  assignments	(see  Variable
       Assignments  below) or a sequence of blank separated words which may be
       preceded by a list of variable  assignments  (see  Environment  below).
       The  first  word	 specifies  the	 name  of  the command to be executed.
       Except as specified below, the remaining words are passed as  arguments
       to  the invoked command.	 The command name is passed as argument 0 (see
       exec(2)).  The value of a simple-command is its exit status;  0-255  if
       it  terminates  normally;  256+signum  if it terminates abnormally (the
       name of the signal corresponding to the exit status can be obtained via
       the -l option of the kill built-in utility).

       A  pipeline  is a sequence of one or more commands separated by |.  The
       standard output of each command but the last is connected by a  pipe(2)
       to the standard input of the next command.  Each command, except possi-
       bly the last, is run as a separate process; the	shell  waits  for  the
       last  command  to terminate.  The exit status of a pipeline is the exit
       status of the last command unless the pipefail option is enabled.  Each
       pipeline	 can be preceded by the reserved word !	 which causes the exit
       status of the pipeline to become 0 if the exit status of the last  com-
       mand is non-zero, and 1 if the exit status of the last command is 0.

       A  list	is  a sequence of one or more pipelines separated by ;, &, |&,
       &&, or ||, and optionally terminated by ;, &, or	 |&.   Of  these  five
       symbols,	 ;,  &, and |& have equal precedence, which is lower than that
       of && and ||.  The symbols && and || also  have	equal  precedence.   A
       semicolon (;) causes sequential execution of the preceding pipeline; an
       ampersand (&) causes asynchronous execution of the  preceding  pipeline
       (i.e.,  the shell does not wait for that pipeline to finish).  The sym-
       bol |& causes asynchronous execution of the preceding pipeline  with  a
       two-way	pipe  established  to the parent shell; the standard input and
       output of the spawned pipeline can be written to and read from  by  the
       parent shell by applying the redirection operators <& and >& with arg p
       to commands and by using -p option of the built-in  commands  read  and
       print described later.  The symbol && (||) causes the list following it
       to be executed only if the preceding pipeline returns a zero (non-zero)
       value.	One  or more new-lines may appear in a list instead of a semi-
       colon, to delimit a command.  The first item  of the first pipeline  of
       a  list	that is a simple command not beginning with a redirection, and
       not occuring within a while, until, or if list, can be  prededed	 by  a
       semicolon.   This  semicolon  is	 ignored  unless  the showme option is
       enabled as described with the set built-in below.

       A command is either a simple-command or one of the  following.	Unless
       otherwise  stated,  the value returned by a command is that of the last
       simple-command executed in the command.

       for vname [ in word ... ] ;do list ;done
	      Each time a for command is executed, vname is set	 to  the  next
	      word  taken  from the in word list.  If in word ...  is omitted,
	      then the for command executes the do list once  for  each	 posi-
	      tional  parameter	 that  is  set	starting from 1 (see Parameter
	      Expansion below).	 Execution ends when there are no  more	 words
	      in the list.

       for (( [expr1] ; [expr2] ; [expr3] )) ;do list ;done
	      The  arithmetic  expression expr1 is evaluated first (see Arith-
	      metic evaluation below).	The  arithmetic	 expression  expr2  is
	      repeatedly  evaluated  until  it evaluates to zero and when non-
	      zero, list is executed and the arithmetic expression expr3 eval-
	      uated.   If  any expression is omitted, then it behaves as if it
	      evaluated to 1.

       select vname [ in word ... ] ;do list ;done
	      A select command prints on standard error	 (file	descriptor  2)
	      the set of words, each preceded by a number.  If in word ...  is
	      omitted, then the positional parameters starting from 1 are used
	      instead  (see  Parameter	Expansion  below).   The PS3 prompt is
	      printed and a line is read from the  standard  input.   If  this
	      line consists of the number of one of the listed words, then the
	      value of the variable vname is set to the word corresponding  to
	      this  number.   If  this	line  is  empty, the selection list is
	      printed again.  Otherwise the value of the variable vname is set
	      to  null.	  The contents of the line read from standard input is
	      saved in the variable REPLY.  The	 list  is  executed  for  each
	      selection	 until	a break or end-of-file is encountered.	If the
	      REPLY variable is set to null by the execution of list, then the
	      selection	 list  is printed before displaying the PS3 prompt for
	      the next selection.

       case word in [ [(]pattern [ | pattern ] ... ) list ;; ] ... esac
	      A case command executes the list associated with the first  pat-
	      tern that matches word.  The form of the patterns is the same as
	      that used for file-name generation  (see	File  Name  Generation
	      below).	The ;; operator causes execution of case to terminate.
	      If ;& is used in place of ;; the next subsequent list,  if  any,
	      is executed.

       if list ;then list [ ;elif list ;then list ] ... [ ;else list ] ;fi
	      The list following if is executed and, if it returns a zero exit
	      status, the list following the first then is  executed.	Other-
	      wise,  the  list following elif is executed and, if its value is
	      zero, the list following the next	 then  is  executed.   Failing
	      each successive elif list, the else list is executed.  If the if
	      list has non-zero exit status and there is no  else  list,  then
	      the if command returns a zero exit status.

       while list ;do list ;done
       until list ;do list ;done
	      A	 while	command repeatedly executes the while list and, if the
	      exit status of the last command in the list  is  zero,  executes
	      the  do  list; otherwise the loop terminates.  If no commands in
	      the do list are executed, then the while command returns a  zero
	      exit  status;  until may be used in place of while to negate the
	      loop termination test.

       ((expression))
	      The expression is evaluated using the rules for arithmetic eval-
	      uation  described below.	If the value of the arithmetic expres-
	      sion is non-zero, the exit status is 0, otherwise the exit  sta-
	      tus is 1.

       (list)
	      Execute list in a separate environment.  Note, that if two adja-
	      cent open parentheses are needed for nesting, a  space  must  be
	      inserted	to  avoid  evaluation  as  an  arithmetic  command  as
	      described above.

       { list;}
	      list is simply executed.	Note that unlike the metacharacters  (
	      and  ),  { and } are reserved words and must occur at the begin-
	      ning of a line or after a ; in order to be recognized.

       [[ expression ]]
	      Evaluates expression and returns a zero exit status when expres-
	      sion is true.  See Conditional Expressions below, for a descrip-
	      tion of expression.

       function varname { list ;}
       varname () { list ;}
	      Define a function which is referenced by	varname.   A  function
	      whose  varname contains a .  is called a discipline function and
	      the portion of the varname preceding the last .  must  refer  to
	      an  existing  variable.  The body of the function is the list of
	      commands between { and }.	 A function defined with the  function
	      varname syntax can also be used as an argument to the .  special
	      built-in command to get the equivalent behavior as if  the  var-
	      name() syntax were used to define it.  (See Functions below.)

       time [ pipeline ]
	      If  pipeline is omitted the user and system time for the current
	      shell and completed  child  processes  is	 printed  on  standard
	      error.   Otherwise, pipeline is executed and the elapsed time as
	      well as the user and system time are printed on standard	error.
	      The TIMEFORMAT variable may be set to a format string that spec-
	      ifies how the timing information should be displayed.  See Shell
	      Variables below for a description of the TIMEFORMAT variable.

       The  following reserved words are recognized as reserved only when they
       are the first word of a command and are not quoted:

       if then else elif fi case esac for while until do  done	{  }  function
       select time [[ ]] !

   Variable Assignments.
       One  or	more variable assignments can start a simple command or can be
       arguments to the typeset, export, or  readonly  special	built-in  com-
       mands.  The syntax for an assignment is of the form:

       varname=word
       varname[word]=word
	      No space is permitted between varname and the = or between = and
	      word.

       varname=(assign_list)
	      No space is permitted between varname and the =.	An assign_list
	      can be one of the following:
		      word ...
			     Indexed array assignment.
		      [word]=word ...
			     Associative  array	 assignment.   If  preceded by
			     typeset -a this  will  create  an	indexed	 array
			     instead.
		      assignment ...
			     Compound  variable	 assignment.   This  creates a
			     compound variable varname with  sub-variables  of
			     the  form	varname.name,  where  name is the name
			     portion of assignment.  The value of varname will
			     contain  all the assignment elements.  Additional
			     assignments made to sub-variables of varname will
			     also  be  displayed  as part of the value of var-
			     name.  If no assignments are  specified,  varname
			     will  be a compound variable allowing subsequence
			     child elements to be defined.
		      typeset [options] assignment ...
			     Nested variable assignment.  Multiple assignments
			     can  be specified by separating each of them with
			     a ;.  The previous	 value	is  unset  before  the
			     assignment.

       In addition, a += can be used in place of the = to signify adding to or
       appending to the previous value.	 When += is applied to	an  arithmetic
       type,  word  is	evaluated as an arithmetic expression and added to the
       current value.  When applied to a string variable, the value defined by
       word  is appended to the value.	For compound assignments, the previous
       value is not unset and the new values are appended to the current  ones
       provided that the types are compatible.

   Comments.
       A  word beginning with # causes that word and all the following charac-
       ters up to a new-line to be ignored.
   Aliasing.
       The first word of each command is replaced by the text of an  alias  if
       an alias for this word has been defined.	 An alias name consists of any
       number of characters excluding metacharacters, quoting characters, file
       expansion  characters,  parameter  expansion  and  command substitution
       characters, and =.  The replacement string can contain any valid	 shell
       script  including  the  metacharacters listed above.  The first word of
       each command in the replaced text, other	 than  any  that  are  in  the
       process	of  being  replaced,  will be tested for aliases.  If the last
       character of the alias value is a blank then  the  word	following  the
       alias will also be checked for alias substitution.  Aliases can be used
       to redefine built-in commands  but  cannot  be  used  to	 redefine  the
       reserved	 words	listed	above.	Aliases can be created and listed with
       the alias command and can be removed with the unalias command.
       Aliasing is performed when scripts are read, not while  they  are  exe-
       cuted.	Therefore,  for	 an alias to take effect, the alias definition
       command has to be executed before  the  command	which  references  the
       alias is read.
       The  following  aliases are compiled into the shell but can be unset or
       redefined:
			   autoload='typeset -fu'
			   command='command  '
			   fc=hist
			   float='typeset -lE'
			   functions='typeset -f'
			   hash='alias -t --'
			   history='hist -l'
			   integer='typeset -li'
			   nameref='typeset -n'
			   nohup='nohup	 '
			   r='hist -s'
			   redirect='command exec'
			   source='command .'
			   stop='kill -s STOP'
			   suspend='kill -s STOP $$'
			   times='{ { time;} 2>&1;}'
			   type='whence -v'

   Tilde Substitution.
       After alias substitution is performed, each word is checked to  see  if
       it begins with an unquoted ~.  For tilde substitution, word also refers
       to the word portion of parameter	 expansion  (see  Parameter  Expansion
       below).	 If  it	 does, then the word up to a / is checked to see if it
       matches a user name in the password database (See getpwname(3).)	 If  a
       match  is  found,  the ~ and the matched login name are replaced by the
       login directory of the matched user.  If no match is found, the	origi-
       nal  text  is  left  unchanged.	 A ~ by itself, or in front of a /, is
       replaced by $HOME.  A ~ followed by a + or - is replaced by  the	 value
       of $PWD and $OLDPWD respectively.

       In  addition,  when expanding a variable assignment, tilde substitution
       is attempted when the value of the assignment begins with a ~, and when
       a ~ appears after a :.  The : also terminates a ~ login name.

   Command Substitution.
       The  standard output from a command enclosed in parentheses preceded by
       a dollar sign ( $() ) or a pair of grave accents (``) may  be  used  as
       part  or	 all of a word; trailing new-lines are removed.	 In the second
       (obsolete) form, the string between the quotes is processed for special
       quoting	characters before the command is executed (see Quoting below).
       The command substitution $(cat file) can be replaced by the  equivalent
       but  faster  $(<file).	The command substitution $(n<#) will expand to
       the current byte offset for file descriptor n.

   Arithmetic Substitution.
       An arithmetic expression enclosed in double parentheses preceded	 by  a
       dollar  sign  (	$(())  )  is  replaced	by the value of the arithmetic
       expression within the double parentheses.

   Process Substitution.
       This feature is only available on versions of the UNIX operating system
       that support the /dev/fd directory for naming open files.  Each command
       argument of the form <(list) or >(list) will  run  process  list	 asyn-
       chronously  connected  to  some file in /dev/fd.	 The name of this file
       will become the argument to  the	 command.   If	the  form  with	 >  is
       selected	 then  writing on this file will provide input for list.  If <
       is used, then the file passed as an argument will contain the output of
       the list process.  For example,

	      paste  <(cut  -f1	 file1)	 <(cut	-f3  file2)  | tee >(process1)
	      >(process2)

       cuts fields 1 and 3 from the files file1 and file2 respectively, pastes
       the  results  together,	and  sends  it	to  the processes process1 and
       process2, as well as putting it onto the standard  output.   Note  that
       the  file,  which  is  passed  as an argument to the command, is a UNIX
       pipe(2) so programs that expect to lseek(2) on the file will not	 work.

   Parameter Expansion.
       A parameter is a variable, one or more digits, or any of the characters
       *, @, #, ?, -, $, and !.	 A variable is denoted by a vname.  To	create
       a variable whose vname contains a ., a variable whose vname consists of
       everything before the last . must already  exist.   A  variable	has  a
       value  and  zero	 or more attributes.  Variables can be assigned values
       and attributes by using the  typeset  special  built-in	command.   The
       attributes  supported by the shell are described later with the typeset
       special	built-in  command.   Exported  variables   pass	  values   and
       attributes to the environment.

       The  shell supports both indexed and associative arrays.	 An element of
       an array variable is referenced by a subscript.	 A  subscript  for  an
       indexed	array  is  denoted by an arithmetic expression (see Arithmetic
       evaluation below) between a [ and a ].  To assign values to an  indexed
       array,  use set -A vname	 value ... .  The value of all subscripts must
       be in the range of 0 through 1,048,575.	Indexed	 arrays	 need  not  be
       declared.   Any reference to a variable with a valid subscript is legal
       and an array will be created if necessary.

       An associative array is created with the -A option to typeset.  A  sub-
       script for an associative array is denoted by a string enclosed between
       [ and ].

       Referencing any array without a subscript is equivalent to  referencing
       the array with subscript 0.

       The value of a variable may be assigned by writing:

	      vname=value [ vname=value ] ...

       or
	      vname[subscript]=value [ vname[subscript]=value ] ...
       Note that no space is allowed before or after the =.
       A  nameref  is  a  variable that is a reference to another variable.  A
       nameref is created with the -n attribute of typeset.  The value of  the
       variable	 at  the time of the typeset command becomes the variable that
       will be referenced whenever the nameref variable is used.  The name  of
       a  nameref  cannot  contain a ..	 When a variable or function name con-
       tains a ., and the portion of the name up to the first  .  matches  the
       name  of	 a  nameref, the variable referred to is obtained by replacing
       the nameref portion with the name of the	 variable  referenced  by  the
       nameref.	  If a nameref is used as the index of a for loop, a name ref-
       erence is established for each item in the list.	 A nameref provides  a
       convenient way to refer to the variable inside a function whose name is
       passed as an argument to a function.  For example, if  the  name	 of  a
       variable is passed as the first argument to a function, the command
	      typeset -n var=$1
       inside the function causes references and assignments to var to be ref-
       erences and assignments to the variable whose name has been  passed  to
       the function.
       If  either  of the floating point attributes, -E, or -F, or the integer
       attribute, -i, is set for vname, then the value is  subject  to	arith-
       metic evaluation as described below.
       Positional  parameters, parameters denoted by a number, may be assigned
       values with the set special built-in command.  Parameter $0 is set from
       argument zero when the shell is invoked.
       The character $ is used to introduce substitutable parameters.
       ${parameter}
	      The  shell reads all the characters from ${ to the matching } as
	      part of the same word even if it contains braces or  metacharac-
	      ters.   The value, if any, of the parameter is substituted.  The
	      braces are required when parameter  is  followed	by  a  letter,
	      digit,  or  underscore  that is not to be interpreted as part of
	      its name, when the variable name contains a ..  The  braces  are
	      also  required  when a variable is subscripted unless it is part
	      of an Arithmetic Expression or  a	 Conditional  Expression.   If
	      parameter	 is one or more digits then it is a positional parame-
	      ter.  A positional parameter of more  than  one  digit  must  be
	      enclosed	in braces.  If parameter is * or @, then all the posi-
	      tional parameters, starting with $1, are substituted  (separated
	      by  a  field  separator character).  If an array vname with sub-
	      script * or @ is used, then the value for each of	 the  elements
	      is substituted, separated by the first character of the value of
	      IFS.
       ${#parameter}
	      If parameter is * or @, the number of positional	parameters  is
	      substituted.   Otherwise, the length of the value of the parame-
	      ter is substituted.
       ${#vname[*]}
       ${#vname[@]}
	      The number of elements in the array vname is substituted.

       ${!vname}
	      Expands to the name of the variable referred to by vname.	  This
	      will be vname except when vname is a name reference.

       ${!vname[subscript]}
	      Expands  to  name	 of  the subscript unless subscript is * or @.
	      When subscript is *, the list of array subscripts for  vname  is
	      generated.   For a variable that is not an array, the value is 0
	      if the variable is set.  Otherwise it is null.   When  subscript
	      is  @,  same  as	above, except that when used in double quotes,
	      each array subscript yields a separate argument.

       ${!prefix*}
	      Expands to the names of the variables  whose  names  begin  with
	      prefix.

       ${parameter:-word}
	      If  parameter  is set and is non-null then substitute its value;
	      otherwise substitute word.

       ${parameter:=word}
	      If parameter is not set or is null then  set  it	to  word;  the
	      value  of the parameter is then substituted.  Positional parame-
	      ters may not be assigned to in this way.

       ${parameter:?word}
	      If parameter is set and is non-null then substitute  its	value;
	      otherwise,  print	 word and exit from the shell (if not interac-
	      tive).  If word is omitted then a standard message is printed.

       ${parameter:+word}
	      If parameter is set and is non-null then substitute word; other-
	      wise substitute nothing.

       In the above, word is not evaluated unless it is to be used as the sub-
       stituted string, so that, in the following  example,  pwd  is  executed
       only if d is not set or is null:

	      print ${d:-$(pwd)}

       If  the	colon  (  :  ) is omitted from the above expressions, then the
       shell only checks whether parameter is set or not.

       ${parameter:offset:length}
       ${parameter:offset}
	      Expands to the portion of the value of parameter starting at the
	      character (counting from 0) determined by expanding offset as an
	      arithmetic expression and consisting of the number of characters
	      determined  by  the arithmetic expression defined by length.  In
	      the second form, the remainder of the value is used.  If A nega-
	      tive  offset  counts  backwards from the end of parameter.  Note
	      that one or more blanks is required in front of a minus sign  to
	      prevent  the  shell  from	 interpreting  the operator as :-.  If
	      parameter is * or @, or is an array name indexed by * or @, then
	      offset  and  length  refer to the array index and number of ele-
	      ments respectively.  A negative offset is taken relative to  one
	      greater  than  the  highest  subscript  for indexed arrays.  The
	      order for associate arrays is unspecified.
       ${parameter#pattern}
       ${parameter##pattern}
	      If the shell pattern matches  the	 beginning  of	the  value  of
	      parameter,  then the value of this expansion is the value of the
	      parameter with the matched portion deleted; otherwise the	 value
	      of  this parameter is substituted.  In the first form the small-
	      est matching pattern is deleted  and  in	the  second  form  the
	      largest matching pattern is deleted.  When parameter is @, *, or
	      an array variable with subscript @ or *, the substring operation
	      is applied to each element in turn.

       ${parameter%pattern}
       ${parameter%%pattern}
	      If  the shell pattern matches the end of the value of parameter,
	      then the value of this expansion is the value of	the  parameter
	      with the matched part deleted; otherwise substitute the value of
	      parameter.  In the first form the smallest matching  pattern  is
	      deleted  and  in the second form the largest matching pattern is
	      deleted.	When parameter is @, *, or an array variable with sub-
	      script  @	 or *, the substring operation is applied to each ele-
	      ment in turn.

       ${parameter/pattern/string}
       ${parameter//pattern/string}
       ${parameter/#pattern/string}
       ${parameter/%pattern/string}
	      Expands parameter and replaces the longest match of pattern with
	      the  given  string.  Each occurrence of \n in string is replaced
	      by the portion of parameter that matches the  n-th  sub-pattern.
	      In  the  first  form,  only  the	first occurrence of pattern is
	      replaced.	 In  the  second  form,	 each  match  for  pattern  is
	      replaced by the given string.  The third form restricts the pat-
	      tern match to the beginning of the string while the fourth  form
	      restricts	 the  pattern  match  to  the end of the string.  When
	      string is null, the pattern will be deleted and the /  in	 front
	      of  string  may be omitted.  When parameter is @, *, or an array
	      variable with subscript @ or *, the  substitution	 operation  is
	      applied  to each element in turn.	 In this case, the string por-
	      tion of word will be re-evaluated for each element.

       The following parameters are automatically set by the shell:
	      #	     The number of positional parameters in decimal.
	      -	     Options supplied to the shell on invocation or by the set
		     command.
	      ?	     The  decimal value returned by the last executed command.
	      $	     The process number of this shell.
	      _	     Initially, the value of _ is an absolute pathname of  the
		     shell  or script being executed as passed in the environ-
		     ment.  Subsequently it is assigned the last  argument  of
		     the previous command.  This parameter is not set for com-
		     mands which are asynchronous.   This  parameter  is  also
		     used  to  hold  the  name	of the matching MAIL file when
		     checking for mail.
	      !	     The process number of the last background command invoked
		     or	 the most recent job put in the background with the bg
		     built-in command.
	      .sh.command
		     When processing a DEBUG trap, this variable contains  the
		     current command line that is about to run.
	      .sh.edchar
		     This  variable contains the value of the keyboard charac-
		     ter (or sequence of characters if the first character  is
		     an	 ESC, ascii 033) that has been entered when processing
		     a KEYBD trap (see Key Bindings below).  If the  value  is
		     changed  as  part	of the trap action, then the new value
		     replaces the key (or key sequence) that caused the	 trap.
	      .sh.edcol
		     The  character  position of the cursor at the time of the
		     most recent KEYBD trap.
	      .sh.edmode
		     The value is set to ESC  when  processing	a  KEYBD  trap
		     while  in	vi insert mode.	 (See Vi Editing Mode  below.)
		     Otherwise, .sh.edmode is null  when  processing  a	 KEYBD
		     trap.
	      .sh.edtext
		     The  characters  in  the  input buffer at the time of the
		     most recent KEYBD trap.  The value is null when not  pro-
		     cessing a KEYBD trap.
	      .sh.file
		     The  pathname  of the file than contains the current com-
		     mand.
	      .sh.fun
		     The name of the current function that is being  executed.
	      .sh.match
		     An	 indexed  array which stores the most recent match and
		     sub-pattern matches  after	 conditional  pattern  matches
		     that match and after variables expansions using the oper-
		     ators #, %, or /.	The 0-th element stores	 the  complete
		     match  and	 the  i-th.  element stores the i-th submatch.
		     The .sh.match variable becomes unset  when	 the  variable
		     that has expanded is assigned a new value.
	      .sh.name
		     Set to the name of the variable at the time that a disci-
		     pline function is invoked.
	      .sh.subscript
		     Set to the name subscript of the  variable	 at  the  time
		     that a discipline function is invoked.
	      .sh.subshell
		     The current depth for subshells and command substitution.
	      .sh.value
		     Set to the value of the variable at the time that the set
		     or append discipline function is invoked.
	      .sh.version
		     Set to a value that identifies the version of this shell.
	      LINENO The current line number within  the  script  or  function
		     being executed.
	      OLDPWD The previous working directory set by the cd command.
	      OPTARG The  value	 of  the last option argument processed by the
		     getopts built-in command.
	      OPTIND The index of the last option argument  processed  by  the
		     getopts built-in command.
	      PPID   The process number of the parent of the shell.
	      PWD    The present working directory set by the cd command.
	      RANDOM Each  time this variable is referenced, a random integer,
		     uniformly distributed between 0 and 32767, is  generated.
		     The  sequence  of	random	numbers	 can be initialized by
		     assigning a numeric value to RANDOM.
	      REPLY  This variable is set by the select statement and  by  the
		     read built-in command when no arguments are supplied.
	      SECONDS
		     Each time this variable is referenced, the number of sec-
		     onds since shell invocation is returned.  If  this	 vari-
		     able  is  assigned	 a value, then the value returned upon
		     reference will be the value that was  assigned  plus  the
		     number of seconds since the assignment.

       The following variables are used by the shell:
	      CDPATH The search path for the cd command.
	      COLUMNS
		     If	 this variable is set, the value is used to define the
		     width of the edit window for the shell edit modes and for
		     printing select lists.
	      EDITOR If	 the  VISUAL  variable	is  not set, the value of this
		     variable will be checked for the  patterns	 as  described
		     with  VISUAL  below  and the corresponding editing option
		     (see Special Command set below) will be turned on.
	      ENV    If this variable is set, then parameter  expansion,  com-
		     mand  substitution,  and arithmetic substitution are per-
		     formed on the value  to  generate	the  pathname  of  the
		     script  that  will	 be executed when the shell is invoked
		     (see Invocation below).  This file is typically used  for
		     alias  and	 function  definitions.	  The default value is
		     $HOME/.kshrc.
	      FCEDIT Obsolete name for the default editor name	for  the  hist
		     command.  FCEDIT is not used when HISTEDIT is set.
	      FIGNORE
		     A	pattern that defines the set of filenames that will be
		     ignored when performing filename matching.
	      FPATH  The search path for function definitions.	 The  directo-
		     ries  in  this path are searched for a file with the same
		     name as the function or command when a function with  the
		     -u	 attribute  is	referenced  and	 when a command is not
		     found.  If an executable file with the name of that  com-
		     mand  is  found, then it is read and executed in the cur-
		     rent environment.	Unlike	PATH,  the  current  directory
		     must be represented explictily by .  rather than by adja-
		     cent : characters or a beginning or ending :.
	      HISTCMD
		     Number of the current command in the history file.
	      HISTEDIT
		     Name for the default editor name for the hist command.
	      HISTFILE
		     If this variable is set when the shell is	invoked,  then
		     the  value	 is the pathname of the file that will be used
		     to	 store	the  command  history  (see  Command  Re-entry
		     below).
	      HISTSIZE
		     If	 this  variable is set when the shell is invoked, then
		     the number of previously entered commands that are acces-
		     sible by this shell will be greater than or equal to this
		     number.  The default is 512.
	      HOME   The default argument (home directory) for the cd command.
	      IFS    Internal  field separators, normally space, tab, and new-
		     line that are used to separate  the  results  of  command
		     substitution  or  parameter  expansion  and  to  separate
		     fields with the built-in command read.  The first charac-
		     ter of the IFS variable is used to separate arguments for
		     the "$*" substitution (see Quoting below).	  Each	single
		     occurrence of an IFS character in the string to be split,
		     that is not in the isspace character class, and any adja-
		     cent  characters in IFS that are in the isspace character
		     class, delimit a field.  One or more  characters  in  IFS
		     that  belong  to  the  isspace character class, delimit a
		     field.   In  addition,  if	 the  same  isspace  character
		     appears  consecutively  inside  IFS,  this	 character  is
		     treated as if it were not in the isspace class,  so  that
		     if	 IFS consists of two tab characters, then two adjacent
		     tab characters delimit a null field.
	      LANG   This variable determines the locale category for any cat-
		     egory  not specifically selected with a variable starting
		     with LC_ or LANG.
	      LC_ALL This variable overrides the value of  the	LANG  variable
		     and any other LC_ variable.
	      LC_COLLATE
		     This  variable determines the locale category for charac-
		     ter collation information.
	      LC_CTYPE
		     This variable determines the locale category for  charac-
		     ter  handling  functions.	 It  determines	 the character
		     classes for pattern matching (see	File  Name  Generation
		     below).
	      LC_NUMERIC
		     This variable determines the locale category for the dec-
		     imal point character.
	      LINES  If this variable is set, the value is used	 to  determine
		     the  column  length  for  printing	 select lists.	Select
		     lists will print vertically  until	 about	two-thirds  of
		     LINES lines are filled.
	      MAIL   If	 this  variable	 is set to the name of a mail file and
		     the MAILPATH variable is not set, then the shell  informs
		     the user of arrival of mail in the specified file.
	      MAILCHECK
		     This  variable specifies how often (in seconds) the shell
		     will check for changes in the modification time of any of
		     the  files	 specified  by the MAILPATH or MAIL variables.
		     The default value is 600  seconds.	  When	the  time  has
		     elapsed  the  shell  will	check  before issuing the next
		     prompt.
	      MAILPATH
		     A colon ( : ) separated list  of  file  names.   If  this
		     variable  is  set, then the shell informs the user of any
		     modifications to the specified files that	have  occurred
		     within the last MAILCHECK seconds.	 Each file name can be
		     followed by a ?  and a message that will be printed.  The
		     message will undergo parameter expansion, command substi-
		     tution, and arithmetic substitution with the variable  $_
		     defined  as  the  name of the file that has changed.  The
		     default message is you have mail in $_.
	      PATH   The search path for commands (see Execution below).   The
		     user  may not change PATH if executing under rksh (except
		     in .profile).
	      PS1    The value of this	variable  is  expanded	for  parameter
		     expansion, command substitution, and arithmetic substitu-
		     tion to define the primary prompt string which by default
		     is	 ``$''.	 The character !  in the primary prompt string
		     is replaced by the command number (see  Command  Re-entry
		     below).   Two successive occurrences of !	will produce a
		     single !  when the prompt string is printed.
	      PS2    Secondary prompt string, by default ``> ''.
	      PS3    Selection prompt string used within  a  select  loop,  by
		     default ``#? ''.
	      PS4    The  value	 of  this  variable  is expanded for parameter
		     evaluation, command substitution, and arithmetic  substi-
		     tution  and precedes each line of an execution trace.  By
		     default, PS4 is ``+ ''.  In addition when PS4  is	unset,
		     the execution trace prompt is also ``+ ''.
	      SHELL  The pathname of the shell is kept in the environment.  At
		     invocation, if the basename  of  this  variable  is  rsh,
		     rksh,  or krsh, then the shell becomes restricted.	 If it
		     is pfsh or pfksh, then the shell becomes a profile	 shell
		     (see pfexec(1)).
	      TIMEFORMAT
		     The  value	 of  this parameter is used as a format string
		     specifying how the timing information for pipelines  pre-
		     fixed  with  the  time reserved word should be displayed.
		     The % character introduces	 a  format  sequence  that  is
		     expanded  to a time value or other information.  The for-
		     mat sequences and their meanings are as follows.
		     %%	       A literal %.
		     %[p][l]R  The elapsed time in seconds.
		     %[p][l]U  The number of CPU seconds spent in user mode.
		     %[p][l]S  The number of CPU seconds spent in system mode.
		     %P	       The CPU percentage, computed as (U + S) / R.

		     The braces denote optional portions.  The optional p is a
		     digit specifying the precision, the number of  fractional
		     digits  after  a  decimal	point.	A value of 0 causes no
		     decimal point or fraction to be output.   At  most	 three
		     places  after  the decimal point can be displayed; values
		     of p greater than 3 are treated as 3.  If p is not speci-
		     fied, the value 3 is used.

		     The optional l specifies a longer format, including hours
		     if greater than zero, minutes, and seconds	 of  the  form
		     HHhMMmSS.FFs.   The  value of p determines whether or not
		     the fraction is included.

		     All other characters are  output  without	change	and  a
		     trailing  newline is added.  If unset, the default value,
		     $'\nreal\t%2lR\nuser\t%2lU\nsys%2lS', is  used.   If  the
		     value is null, no timing information is displayed.

	      TMOUT  If	 set  to  a value greater than zero, TMOUT will be the
		     default timeout value for the read built-in command.  The
		     select  compound  command	terminates after TMOUT seconds
		     when input is from a terminal.  Otherwise, the shell will
		     terminate	if a line is not entered within the prescribed
		     number of seconds while reading from a  terminal.	 (Note
		     that  the	shell can be compiled with a maximum bound for
		     this value which cannot be exceeded.)

	      VISUAL If	 the  value  of	 this  variable	 matches  the  pattern
		     *[Vv][Ii]*,  then	the vi option (see Special Command set
		     below) is turned on.  If the value	 matches  the  pattern
		     *gmacs*  ,	 the  gmacs option is turned on.  If the value
		     matches the pattern *macs*, then the emacs option will be
		     turned  on.   The	value of VISUAL overrides the value of
		     EDITOR.

       The shell gives default values to PATH, PS1, PS2, PS3, PS4,  MAILCHECK,
       FCEDIT,	TMOUT and IFS, while HOME, SHELL, ENV, and MAIL are not set at
       all by the shell (although HOME is set by login(1)).  On	 some  systems
       MAIL and SHELL are also set by login(1).

   Field Splitting.
       After parameter expansion and command substitution, the results of sub-
       stitutions are scanned for the field separator characters (those	 found
       in IFS) and split into distinct fields where such characters are found.
       Explicit null fields ("" or '') are  retained.	Implicit  null	fields
       (those resulting from parameters that have no values or command substi-
       tutions with no output) are removed.

       If the braceexpand (-B) option is set then each of the fields resulting
       from  IFS  are  checked to see if they contain one or more of the brace
       patterns {*,*}, {l1..l2} , {n1..n2} , {n1..n2% fmt} , {n1..n2  ..n3}  ,
       or {n1..n2 ..n3%fmt} , where * represents any character, l1,l2 are let-
       ters and n1,n2,n3 are signed numbers and fmt is a format	 specified  as
       used  by	 printf.   In  each case, fields are created by prepending the
       characters before the { and appending the characters  after  the	 }  to
       each  of	 the  strings generated by the characters between the { and }.
       The resulting fields are checked to see if they	have  any  brace  pat-
       terns.

       In  the first form, a field is created for each string between { and ,,
       between , and ,, and between , and }.  The string represented by *  can
       contain	embedded  matching { and } without quoting.  Otherwise, each {
       and } with * must be quoted.

       In the seconds form, l1 and l2 must both be either upper case  or  both
       be lower case characters in the C locale.  In this case a field is cre-
       ated for each character from l1 thru l2.

       In the remaining forms, a field is created for each number starting  at
       n1 and continuing until it reaches n2 incrementing n1 by n3.  The cases
       where n3 is not specified behave as if n3 where 1 if n1<=n2 and -1 oth-
       erwise.	 If forms which specify %fmt any format flags, widths and pre-
       cisions can be specified and fmt can  end  in  any  of  the  specifiers
       cdiouxX.	  For  example,	 {a,z}{1..5..3%02d}{b..c}x  expands  to	 the 8
       fields, a01bx, a01cx, a04bx, a04cx, z01bx, z01cx, z04bx and z4cx.

   File Name Generation.
       Following splitting, each field is scanned for the characters *, ?,  (,
       and  [  unless  the -f option has been set.  If one of these characters
       appears, then the word is regarded as a pattern.	 Each file name compo-
       nent  that  contains  any  pattern character is replaced with a lexico-
       graphically sorted set of names that  matches  the  pattern  from  that
       directory.   If	no  file  name is found that matches the pattern, then
       that component of the filename is left unchanged unless the pattern  is
       prefixed	 with ~(N) in which case it is removed as described below.  If
       FIGNORE is set, then each file name component that matches the  pattern
       defined by the value of FIGNORE is ignored when generating the matching
       filenames.  The names .	and ..	are also ignored.  If FIGNORE  is  not
       set,  the character .  at the start of each file name component will be
       ignored unless the first character of the pattern corresponding to this
       component  is  the  character  .	 itself.  Note, that for other uses of
       pattern matching the / and .  are not treated specially.

	      *	     Matches any string, including the null string.  When used
		     for filename expansion, if the globstar option is on, two
		     adjacent *'s by itself will match all files and  zero  or
		     more  directories and subdirectories.  If followed by a /
		     than only directories and subdirectories will match.
	      ?	     Matches any single character.
	      [...]  Matches any one of the enclosed characters.   A  pair  of
		     characters separated by - matches any character lexically
		     between the pair, inclusive.  If the first character fol-
		     lowing  the  opening  [  is  a  !	then any character not
		     enclosed is matched.  A - can be included in the  charac-
		     ter set by putting it as the first or last character.
		     Within  [	and ], character classes can be specified with
		     the syntax [:class:] where class is one of the  following
		     classes  defined  in the ANSI-C standard: (Note that word
		     is equivalent to alnum plus the character _).
	      alnum alpha blank cntrl digit  graph  lower  print  punct	 space
	      upper word xdigit
	      Within  [	 and ], an equivalence class can be specified with the
	      syntax [=c=] which matches all characters with the same  primary
	      collation weight (as defined by the current locale) as the char-
	      acter c.
	      Within [ and ], [.symbol.]  matches the collating symbol symbol.
       A  pattern-list	is  a list of one or more patterns separated from each
       other with a & or |.  A & signifies that all patterns must  be  matched
       whereas	|  requires  that only one pattern be matched.	Composite pat-
       terns can be formed with one or more of the following sub-patterns:
	      ?(pattern-list)
		     Optionally matches any one of the given patterns.
	      *(pattern-list)
		     Matches zero or more occurrences of the given patterns.
	      +(pattern-list)
		     Matches one or more occurrences of the given patterns.
	      {n}(pattern-list)
		     Matches n occurrences of the given patterns.
	      {m,n}(pattern-list)
		     Matches from m to n occurrences of	 the  given  patterns.
		     If	 m  is	omitted,  0  will be used.  If n is omitted at
		     least m occurrences will be matched.
	      @(pattern-list)
		     Matches exactly one of the given patterns.
	      !(pattern-list)
		     Matches anything except one of the given patterns.
       By default, each pattern, or sub-pattern will match the longest	string
       possible consistent with generating the longest overall match.  If more
       than one match is possible, the one starting closest to	the  beginning
       of the string will be chosen.   However, for each of the above compound
       patterns a - can be inserted in front of the ( to  cause	 the  shortest
       match to the specified pattern-list to be used.

       When  pattern-list is contained within parenthesis, the backslash char-
       acter \ is treated specially even when inside a character class.	   All
       ANSI-C character escapes are recognized and match the specified charac-
       ter.  In addition the following escape sequences are recognized:
	      \d     Matches any character in the digit class.
	      \D     Matches any character not in the digit class.
	      \s     Matches any character in the space class.
	      \S     Matches any character not in the space class.
	      \w     Matches any character in the word class.
	      \W     Matches any character not in the word class.

       A pattern of the form %(pattern-pair(s)) is a sub-pattern that  can  be
       used to match nested character expressions.  Each pattern-pair is a two
       character sequence which cannot contain & or |.	The first pattern-pair
       specifies  the starting and ending characters for the match.  Each sub-
       sequent pattern-pair represents the beginning and ending characters  of
       a  nested  group	 that  will be skipped over when counting starting and
       ending character matches.  The behavior is unspecified when  the	 first
       character of a pattern-pair is alpha-numeric except for the following:
	      D	     Causes  the  ending character to terminate the search for
		     this pattern without finding a match.
	      E	     Causes the ending	character  to  be  interpreted	as  an
		     escape character.
	      L	     Causes  the ending character to be interpreted as a quote
		     character causing all characters to be ignored when look-
		     ing for a match.
	      Q	     Causes  the ending character to be interpreted as a quote
		     character causing all characters other  than  any	escape
		     character to be ignored when looking for a match.
       Thus,  %({}Q"E\), matches characters starting at { until the matching }
       is found not counting any { or } that is inside a double quoted	string
       or  preceded  by	 the  escape character \.  Without the {} this pattern
       matches any C language string.

       Each sub-pattern in a composite pattern is numbered, starting at 1,  by
       the  location of the ( within the pattern.  The sequence \n, where n is
       a single digit and \n comes after the n-th.  sub-pattern,  matches  the
       same string as the sub-pattern itself.

       Finally	a  pattern can contain sub-patterns of the form ~(options:pat-
       tern-list).  where either options  or  :pattern-list  can  be  omitted.
       Unlike, the other compound patterns, these sub-patterns are not counted
       in the numbered sub-patterns.  If options is present, it can consist of
       one or more of the following:
	      +	     Enable the following options.  This is the default.
	      -	     Disable the following options.
	      E	     The  remainder  of	 the  pattern  uses  extended  regular
		     expression syntax like the egrep(1) command.
	      F	     The remainder of the  pattern  uses  fgrep(1)  expression
		     syntax.
	      G	     The  remainder  of the pattern uses basic regular expres-
		     sion syntax like the grep(1) command.
	      K	     The remainder of the pattern uses shell  pattern  syntax.
		     This is the default.
	      N	     This  is  ignored.	  However, when it is the first letter
		     and is used with file name	 generation,  and  no  matches
		     occur, the file pattern expands to the empty string.
	      i	     Treat the match as case insensitive.
	      g	     File the longest match (greedy).  This is the default.
	      l	     Left anchor the pattern.  This is the default for K style
		     patterns.
	      r	     Right anchor the pattern.	This  is  the  default	for  K
		     style patterns.
       If both options and :pattern-list are specified, then the options apply
       only to	pattern-list.  Otherwise, these options remain in effect until
       they  are disabled by a subsequent ~(...) or at the end of the sub-pat-
       tern containing ~(...).

   Quoting.
       Each of the metacharacters listed earlier (see Definitions above) has a
       special meaning to the shell

       i      Treat the match as case insensitive.

       g      File the longest match (greedy).	This is the default.
       If both options and :pattern-list are specified, then the options apply
       only to	pattern-list.  Otherwise, these options remain in effect until
       they  are disabled by a subsequent ~(...) or at the end of the sub-pat-
       tern containing ~(...).

   Quoting.
       Each of the metacharacters listed earlier (see Definitions above) has a
       special	meaning	 to  the shell and causes termination of a word unless
       quoted.	A character may be quoted (i.e., made to stand for itself)  by
       preceding  it with a \.	The pair \new-line is removed.	All characters
       enclosed between a pair of single quote marks ('') that is not preceded
       by  a  $	 are  quoted.	A single quote cannot appear within the single
       quotes.	A single quoted string preceded by an unquoted $ is  processed
       as an ANSI-C string except for the following:
       \0     Causes the remainder of the string to be ignored.
       \E     Equivalent to the escape character (ascii 033),
       \e     Equivalent to the escape character (ascii 033),
       \cx    Expands to the character control-x.
       \C[.name.]
	      Expands to the collating element name.

       Inside  double  quote  marks  (""),  parameter and command substitution
       occur and \ quotes the characters \, `, ", and $.  A $ in  front	 of  a
       double  quoted string will be ignored in the "C" or "POSIX" locale, and
       may cause the string to be replaced by a locale specific string	other-
       wise.   The  meaning  of $* and $@ is identical when not quoted or when
       used as a variable assignment value or as a file name.	However,  when
       used  as a command argument, "$*" is equivalent to "$1d$2d...", where d
       is the first character of the IFS variable, whereas "$@" is  equivalent
       to  "$1" "$2" ....  Inside grave quote marks (``), \ quotes the charac-
       ters \, `, and $.  If the grave quotes occur within double quotes, then
       \ also quotes the character ".

       The  special  meaning  of  reserved  words or aliases can be removed by
       quoting any character of the reserved word.  The recognition  of	 func-
       tion  names or built-in command names listed below cannot be altered by
       quoting them.

   Arithmetic Evaluation.
       The shell performs arithmetic evaluation for  arithmetic	 substitution,
       to  evaluate  an	 arithmetic command, to evaluate an indexed array sub-
       script, and to evaluate arguments to the built-in  commands  shift  and
       let.   Evaluations  are performed using double precision floating point
       arithmetic or long double precision floating  point  for	 systems  that
       provide	this  data  type.   Floating point constants follow the ANSI-C
       programming language floating  point  conventions.   Integer  constants
       follow  the  ANSI-C  programming	 language integer constant conventions
       although only single byte character constants are recognized and	 char-
       acter  casts  are  not recognized.  In addition constants can be of the
       form [base#]n where base is a decimal number between two and sixty-four
       representing  the  arithmetic base and n is a number in that base.  The
       digits above 9 are represented by the lower  case  letters,  the	 upper
       case  letters,  @, and _ respectively.  For bases less than or equal to
       36, upper and lower case characters can be used interchangeably.

       An arithmetic expression uses the same syntax, precedence, and associa-
       tivity  of  expression as the C language.  All the C language operators
       that apply to floating point quantities can be used.  In addition,  the
       operator	 **  can be used for exponentiation.  It has higher precedence
       than multiplication as is left  associative.   In  addition,  when  the
       value of an arithmetic variable or sub-expression can be represented as
       a long integer, all C language integer  arithmetic  operations  can  be
       performed.   Variables  can  be referenced by name within an arithmetic
       expression without using the parameter expansion syntax.	 When a	 vari-
       able is referenced, its value is evaluated as an arithmetic expression.

       Any of the following math library functions that	 are  in  the  C  math
       library can be used within an arithmetic expression:

       abs  acos  acosh asin asinh atan atan2 atanh cbrt copysign cos cosh erf
       erfc exp exp2 expm1 fabs fdim finite floor fma fmax  fmod  hypot	 ilogb
       int isinf isnan lgamma log log2 logb nearbyint nextafter nexttoward pow
       remainder rint round sin sinh sqrt tan tanh tgamma trunc

       An internal representation of a variable as a double precision floating
       point  can be specified with the -E [n] or -F [n] option of the typeset
       special built-in command.  The -E option causes the  expansion  of  the
       value  to be represented using scientific notation when it is expanded.
       The optional option argument n defines the number of  significant  fig-
       ures.  The -F option causes the expansion to be represented as a float-
       ing decimal number when it is expanded.	The optional option argument n
       defines the number of places after the decimal point in this case.

       An  internal integer representation of a variable can be specified with
       the -i [n]  option  of  the  typeset  special  built-in	command.   The
       optional option argument n specifies an arithmetic base to be used when
       expanding the variable.	If you do not specify an arithmetic base, base
       10 will be used.

       Arithmetic evaluation is performed on the value of each assignment to a
       variable with the -E, -F, or -i attribute.  Assigning a floating	 point
       number  to  a  variable	whose type is an integer causes the fractional
       part to be truncated.

   Prompting.
       When used interactively, the shell prompts with the value of PS1	 after
       expanding  it for parameter expansion, command substitution, and arith-
       metic substitution, before reading a command.  In addition, each single
       !   in the prompt is replaced by the command number.  A !!  is required
       to place !  in the prompt.  If at any time a new-line is typed and fur-
       ther  input  is needed to complete a command, then the secondary prompt
       (i.e., the value of PS2) is issued.

   Conditional Expressions.
       A conditional expression is used with the [[ compound command  to  test
       attributes  of  files and to compare strings.  Field splitting and file
       name generation are not performed on the words between [[ and ]].  Each
       expression  can	be constructed from one or more of the following unary
       or binary expressions:
       string True, if string is not null.
       -a file
	      Same as -e below.	 This is obsolete.
       -b file
	      True, if file exists and is a block special file.
       -c file
	      True, if file exists and is a character special file.
       -d file
	      True, if file exists and is a directory.
       -e file
	      True, if file exists.
       -f file
	      True, if file exists and is an ordinary file.
       -g file
	      True, if file exists and it has its setgid bit set.
       -k file
	      True, if file exists and it has its sticky bit set.
       -n string
	      True, if length of string is non-zero.
       -o ?option
	      True, if option named option is a valid option name.
       -o option
	      True, if option named option is on.
       -p file
	      True, if file exists and is a fifo special file or a pipe.
       -r file
	      True, if file exists and is readable by current process.
       -s file
	      True, if file exists and has size greater than zero.
       -t fildes
	      True, if file descriptor number fildes is	 open  and  associated
	      with a terminal device.
       -u file
	      True, if file exists and it has its setuid bit set.
       -w file
	      True, if file exists and is writable by current process.
       -x file
	      True,  if	 file exists and is executable by current process.  If
	      file exists and is a directory, then true if the current process
	      has permission to search in the directory.
       -z string
	      True, if length of string is zero.
       -L file
	      True, if file exists and is a symbolic link.
       -h file
	      True, if file exists and is a symbolic link.
       -N file
	      True,  if	 file exists and the modification time is greater than
	      the last access time.
       -O file
	      True, if file exists and is owned by the effective  user	id  of
	      this process.
       -G file
	      True,  if	 file exists and its group matches the effective group
	      id of this process.
       -S file
	      True, if file exists and is a socket.
       file1 -nt file2
	      True, if file1 exists and file2 does not, or file1 is newer than
	      file2.
       file1 -ot file2
	      True, if file2 exists and file1 does not, or file1 is older than
	      file2.
       file1 -ef file2
	      True, if file1 and file2 exist and refer to the same file.
       string == pattern
	      True, if string matches pattern.	Any part  of  pattern  can  be
	      quoted to cause it to be matched as a string.  With a successful
	      match to a pattern, the .sh.match array  variable	 will  contain
	      the match and sub-pattern matches.
       string = pattern
	      Same as == above, but is obsolete.
       string != pattern
	      True, if string does not match pattern.  With the string matches
	      the pattern the .sh.match array variable will contain the	 match
	      and sub-pattern matches.
       string =~ ere
	      True  if	string	matches	 the  pattern  ~(E)ere where ere is an
	      extended regular expression.
       string1 < string2
	      True, if string1 comes before string2 based on  ASCII  value  of
	      their characters.
       string1 > string2
	      True,  if	 string1  comes	 after string2 based on ASCII value of
	      their characters.
       The following obsolete arithmetic comparisons are also permitted:
       exp1 -eq exp2
	      True, if exp1 is equal to exp2.
       exp1 -ne exp2
	      True, if exp1 is not equal to exp2.
       exp1 -lt exp2
	      True, if exp1 is less than exp2.
       exp1 -gt exp2
	      True, if exp1 is greater than exp2.
       exp1 -le exp2
	      True, if exp1 is less than or equal to exp2.
       exp1 -ge exp2
	      True, if exp1 is greater than or equal to exp2.

       In each of the above expressions, if file is  of	 the  form  /dev/fd/n,
       where  n is an integer, then the test is applied to the open file whose
       descriptor number is n.

       A compound expression can be constructed from these primitives by using
       any of the following, listed in decreasing order of precedence.
       (expression)
	      True, if expression is true.  Used to group expressions.
       ! expression
	      True if expression is false.
       expression1 && expression2
	      True, if expression1 and expression2 are both true.
       expression1 || expression2
	      True, if either expression1 or expression2 is true.

   Input/Output.
       Before  a  command  is executed, its input and output may be redirected
       using a special notation interpreted by the shell.  The	following  may
       appear  anywhere in a simple-command or may precede or follow a command
       and are not passed on to the invoked  command.	Command	 substitution,
       parameter  expansion,  and arithmetic substitution occur before word or
       digit is used except as noted below.  File name generation occurs  only
       if  the	shell  is  interactive	and the pattern matches a single file.
       Field splitting is not performed.

       In each	of  the	 following  redirections,  if  file  is	 of  the  form
       /dev/sctp/host/port,  /dev/tcp/host/port,  or /dev/udp/host/port, where
       host is a hostname or host address, and port is a service given by name
       or an integer port number, then the redirection attempts to make a tcp,
       sctp or udp connection to the corresponding socket.

       No intervening space is allowed between the characters  of  redirection
       operators.

       <word	     Use file word as standard input (file descriptor 0).

       >word	     Use file word as standard output (file descriptor 1).  If
		     the file does not exist then it is created.  If the  file
		     exists,  and  the	noclobber option is on, this causes an
		     error; otherwise, it is truncated to zero length.

       >|word	     Sames as  >,  except  that	 it  overrides	the  noclobber
		     option.

       >>word	     Use  file	word  as standard output.  If the file exists,
		     then output is appended to it (by first  seeking  to  the
		     end-of-file); otherwise, the file is created.

       <>word	     Open file word for reading and writing as standard input.

       <<[-]word     The shell input is read up to a line that is the same  as
		     word after any quoting has been removed, or to an end-of-
		     file.  No parameter substitution,	command	 substitution,
		     arithmetic	 substitution  or file name generation is per-
		     formed on word.  The resulting document, called  a	 here-
		     document,	becomes	 the standard input.  If any character
		     of word is quoted, then no interpretation is placed  upon
		     the  characters  of  the  document;  otherwise, parameter
		     expansion, command substitution, and arithmetic substitu-
		     tion  occur,  \new-line is ignored, and \ must be used to
		     quote the characters \, $, `.  If - is  appended  to  <<,
		     then all leading tabs are stripped from word and from the
		     document.	If # is appended to <<,	 then  leading	spaces
		     and tabs will be stripped off the first line of the docu-
		     ment and up to an equivalent indentation will be stripped
		     from  the	remaining  lines and from word.	 A tab stop is
		     assumend to occur at every 8 columns for the purposes  of
		     determining the indentation.

       <<<word	     A	short  form of here document in which word becomes the
		     contents of the here-document after any parameter	expan-
		     sion,  command  substitution, and arithmetic substitution
		     occur.

       <&digit	     The standard input is  duplicated	from  file  descriptor
		     digit  (see  dup(2)).   Similarly for the standard output
		     using >&digit.

       <&digit-	     The file descriptor given by digit is moved  to  standard
		     input.  Similarly for the standard output using >&digit-.

       <&-	     The standard input is closed.  Similarly for the standard
		     output using >&-.

       <&p	     The input from the co-process is moved to standard input.

       >&p	     The output to the co-process is moved to standard output.

       <#((expr))    Evaluate  arithmetic  expression  expr  and position file
		     descriptor 0 to the resulting value bytes from the	 start
		     of	 the  file.  The variables CUR and EOF evaluate to the
		     current offset and end-of-file offset  respectively  when
		     evaluating expr.

       >#((offset))  The same as <# except applies to file descriptor 1.

       <#pattern     Seeks  forward to the beginning of the next line contain-
		     ing pattern.

       <##pattern    The same as <# except that the portion of the  file  that
		     is skipped is copied to standard output.

       If  one of the above is preceded by a digit, with no intervening space,
       then the file descriptor number referred to is that  specified  by  the
       digit (instead of the default 0 or 1).  If one of the above, other than
       >&- and the ># and ># forms, is preceded by {varname} with no interven-
       ing  space,  then a file descriptor number > 10 will be selected by the
       shell and stored in the variable varname.  If >&- or the any of the  >#
       and  ># forms is preceded by {varname} the value of varname defines the
       file descriptor to close or position.  For example:

	      ... 2>&1

       means file descriptor 2 is to be opened for writing as a	 duplicate  of
       file descriptor 1 and

	      exec {n}<file

       means  open  file  named file for reading and store the file descriptor
       number in variable n.

       The order in which redirections	are  specified	is  significant.   The
       shell  evaluates	 each  redirection  in	terms of the (file descriptor,
       file) association at the time of evaluation.  For example:

	      ... 1>fname 2>&1

       first associates file descriptor 1 with file fname.  It then associates
       file descriptor 2 with the file associated with file descriptor 1 (i.e.
       fname).	If the order of redirections were reversed, file descriptor  2
       would  be  associated with the terminal (assuming file descriptor 1 had
       been) and then file descriptor 1 would be associated with file fname.

       If a command is followed by & and job control is not active,  then  the
       default	standard  input	 for  the command is the empty file /dev/null.
       Otherwise, the environment for the execution of a command contains  the
       file  descriptors  of  the  invoking  shell as modified by input/output
       specifications.

   Environment.
       The environment (see environ(7)) is a list of name-value pairs that  is
       passed  to  an  executed	 program  in the same way as a normal argument
       list.  The names must be	 identifiers  and  the	values	are  character
       strings.	 The shell interacts with the environment in several ways.  On
       invocation, the shell scans the environment and creates a variable  for
       each  name  found, giving it the corresponding value and attributes and
       marking it export.  Executed commands inherit the environment.  If  the
       user  modifies the values of these variables or creates new ones, using
       the export or typeset -x commands, they become part of the environment.
       The  environment	 seen  by any executed command is thus composed of any
       name-value pairs originally inherited by the shell, whose values may be
       modified	 by  the current shell, plus any additions which must be noted
       in export or typeset -x commands.

       The environment for any simple-command or function may be augmented  by
       prefixing it with one or more variable assignments.  A variable assign-
       ment argument is a word of the form identifier=value.  Thus:

	      TERM=450 cmd args			 and
	      (export TERM; TERM=450; cmd args)

       are equivalent (as far as the  above  execution	of  cmd	 is  concerned
       except for special built-in commands listed below - those that are pre-
       ceded with a dagger).

       If the obsolete -k option is set, all variable assignment arguments are
       placed  in  the environment, even if they occur after the command name.
       The following first prints a=b c and then c:

	      echo a=b c
	      set -k
	      echo a=b c
       This feature is intended for use with scripts written  for  early  ver-
       sions  of the shell and its use in new scripts is strongly discouraged.
       It is likely to disappear someday.

   Functions.
       For historical reasons, there are two ways  to  define  functions,  the
       name()  syntax  and the function name syntax, described in the Commands
       section above.  Shell functions are  read  in  and  stored  internally.
       Alias names are resolved when the function is read.  Functions are exe-
       cuted like commands with the arguments passed as positional parameters.
       (See Execution below.)

       Functions  defined  by the function name syntax and called by name exe-
       cute in the same process as the caller and share all files and  present
       working	directory  with	 the  caller.	Traps caught by the caller are
       reset to their default action inside the function.   A  trap  condition
       that  is	 not  caught or ignored by the function causes the function to
       terminate and the condition to be passed on to the caller.  A  trap  on
       EXIT set inside a function is executed in the environment of the caller
       after the function completes.  Ordinarily, variables are shared between
       the  calling  program  and  the function.  However, the typeset special
       built-in command used within a function defines local  variables	 whose
       scope  includes	the current function.  They can be passed to functions
       that they call in the variable assignment list the precedes the call or
       as arguments passed as name references.	Errors within functions return
       control to the caller.

       Functions defined with the name() syntax and functions defined with the
       function	 name syntax that are invoked with the .  special built-in are
       executed in the caller's environment and share all variables and	 traps
       with  the  caller.   Errors  within these function executions cause the
       script that contains them to abort.

       The special built-in command return is used  to	return	from  function
       calls.

       Function	 names	can  be listed with the -f or +f option of the typeset
       special built-in command.  The text of functions, when available,  will
       also  be listed with -f.	 Functions can be undefined with the -f option
       of the unset special built-in command.

       Ordinarily, functions are unset when the shell executes a shell script.
       Functions  that	need  to be defined across separate invocations of the
       shell should be placed in a directory and  the  FPATH  variable	should
       contain	the name of this directory.  They may also be specified in the
       ENV file.

   Discipline Functions.
       Each variable can have zero or  more  discipline	 functions  associated
       with  it.   The	shell  initially understands the discipline names get,
       set, append, and unset but on most systems others can be added  at  run
       time  via the C programming interface extension provided by the builtin
       built-in utility.  If the get discipline is defined for a variable,  it
       is  invoked whenever the given variable is referenced.  If the variable
       .sh.value is assigned a value inside the discipline function, the  ref-
       erenced	variable will evaluate to this value instead.  If the set dis-
       cipline is defined for a variable, it is	 invoked  whenever  the	 given
       variable	 is assigned a value.  If the append discipline is defined for
       a variable, it is invoked whenever a value is  appended	to  the	 given
       variable.   The	variable  .sh.value is given the value of the variable
       before invoking the discipline, and the variable will be	 assigned  the
       value  of  .sh.value  after  the discipline completes.  If .sh.value is
       unset inside the discipline, then that  value  is  unchanged.   If  the
       unset  discipline is defined for a variable, it is invoked whenever the
       given variable is unset.	 The variable will not be unset unless	it  is
       unset explicitly from within this discipline function.

       The  variable  .sh.name contains the name of the variable for which the
       discipline function is called, .sh.subscript is the  subscript  of  the
       variable,  and  .sh.value  will contain the value being assigned inside
       the  .set  discipline  function.	  For  the  set	 discipline,  changing
       .sh.value will change the value that gets assigned.

   Jobs.
       If  the	monitor option of the set command is turned on, an interactive
       shell associates a job with each pipeline.  It keeps a table of current
       jobs,  printed by the jobs command, and assigns them small integer num-
       bers.  When a job is started asynchronously with &, the shell prints  a
       line which looks like:

	    [1] 1234

       indicating that the job which was started asynchronously was job number
       1 and had one (top-level) process, whose process id was 1234.

       This paragraph and the next require features that are not in  all  ver-
       sions  of UNIX and may not apply.  If you are running a job and wish to
       do something else you may hit the key ^Z (control-Z) which sends a STOP
       signal  to the current job.  The shell will then normally indicate that
       the job has been `Stopped', and print another  prompt.	You  can  then
       manipulate the state of this job, putting it in the background with the
       bg command, or run some other commands and then	eventually  bring  the
       job  back  into	the  foreground	 with the foreground command fg.  A ^Z
       takes effect immediately and is like an interrupt in that pending  out-
       put and unread input are discarded when it is typed.

       A  job  being  run in the background will stop if it tries to read from
       the terminal.  Background jobs are normally allowed to produce  output,
       but this can be disabled by giving the command stty tostop.  If you set
       this tty option, then background jobs will stop when they try  to  pro-
       duce output like they do when they try to read input.

       There  are  several  ways  to refer to jobs in the shell.  A job can be
       referred to by the process id of any process of the job or  by  one  of
       the following:
       %number
	      The job with the given number.
       %string
	      Any job whose command line begins with string.
       %?string
	      Any job whose command line contains string.
       %%     Current job.
       %+     Equivalent to %%.
       %-     Previous job.

       The shell learns immediately whenever a process changes state.  It nor-
       mally informs you whenever a job becomes blocked	 so  that  no  further
       progress is possible, but only just before it prints a prompt.  This is
       done so that it does not	 otherwise  disturb  your  work.   The	notify
       option  of  the	set command causes the shell to print these job change
       messages as soon as they occur.

       When the monitor option is on, each background job that completes trig-
       gers any trap set for CHLD.

       When  you try to leave the shell while jobs are running or stopped, you
       will be warned that `You have stopped(running) jobs.'  You may use  the
       jobs  command  to  see  what  they are.	If you immediately try to exit
       again, the shell will not warn you a second time, and the stopped  jobs
       will be terminated.  When a login shell receives a HUP signal, it sends
       a HUP signal to each job that has not been  disowned  with  the	disown
       built-in command described below.

   Signals.
       The INT and QUIT signals for an invoked command are ignored if the com-
       mand is followed by & and the monitor option is not active.  Otherwise,
       signals have the values inherited by the shell from its parent (but see
       also the trap built-in command below).

   Execution.
       Each time a command is read, the above substitutions are	 carried  out.
       If the command name matches one of the Special Built-in Commands listed
       below, it is executed within the current shell process.	Next, the com-
       mand  name is checked to see if it matches a user defined function.  If
       it does, the positional parameters are saved  and  then	reset  to  the
       arguments  of  the  function  call.  A function is also executed in the
       current shell process.  When the function completes or issues a return,
       the  positional parameter list is restored.  For functions defined with
       the function name syntax, any trap set on EXIT within the  function  is
       executed.   The	exit value of a function is the value of the last com-
       mand executed.  If a command name is not a special built-in command  or
       a  user defined function, but it is one of the built-in commands listed
       below, it is executed in the current shell process.

       The shell variable PATH defines the search path for the directory  con-
       taining	the  command.	Alternative directory names are separated by a
       colon (:).   The	 default  path	is  /bin:/usr/bin:  (specifying	 /bin,
       /usr/bin, and the current directory in that order).  The current direc-
       tory can be specified by two or more adjacent colons, or by a colon  at
       the  beginning or end of the path list.	If the command name contains a
       /, then the search path is not used.  Otherwise, each directory in  the
       path is searched for an executable file of the given name that is not a
       directory.  If found, and if the	 shell	determines  that  there	 is  a
       built-in	 version  of a command corresponding to a given pathname, this
       built-in is invoked in the current process.  If found, and this	direc-
       tory  is	 also  contained in the value of the FPATH variable, then this
       file is loaded into the current shell environment as  if	 it  were  the
       argument to the . command except that only preset aliases are expanded,
       and a function of the given name is executed as	described  above.   If
       not  found,  and the file .paths is found, and the this file contains a
       line of the form FPATH=path where path names an existing directory, and
       this  directory	contains  a  file of the given name, then this file is
       loaded into the current shell environment as if it were the argument to
       the . special built-in command and a function of the given name is exe-
       cuted.  Otherwise, if found, a process is created  and  an  attempt  is
       made to execute the command via exec(2).

       When  an	 executable  is	 found,	 the directory where it is found in is
       searched for a file named .paths.  If this file is found	 and  it  con-
       tains  a line of the form BUILTIN_LIB=value , then the library named by
       value will be searched for as if it were an option argument to  builtin
       -f,  and	 if  it contains a built-in of the specified name this will be
       executed instead of a command by this name.  Otherwise, if this file is
       found  and  it  contains	 a line of the form name=value in the first or
       second line, then the environment variable name is modified by prepend-
       ing  the	 directory specified by value to the directory list.  If value
       is not an absolute directory, then it specifies a directory relative to
       the  directory that the executable was found.  If the environment vari-
       able name does not already exist it will be added  to  the  environment
       list for the specified command.

       If  the	file  has  execute  permission but is not an a.out file, it is
       assumed to be a file containing shell commands.	A  separate  shell  is
       spawned	to  read  it.	All non-exported variables are removed in this
       case.  If the shell command file doesn't have read  permission,	or  if
       the  setuid and/or setgid bits are set on the file, then the shell exe-
       cutes an agent whose job it is to set up the  permissions  and  execute
       the  shell  with the shell command file passed down as an open file.  A
       parenthesized command is executed in a sub-shell without removing  non-
       exported variables.

   Command Re-entry.
       The  text  of  the  last HISTSIZE (default 512) commands entered from a
       terminal device is saved in a history file.  The file $HOME/.sh_history
       is  used if the HISTFILE variable is not set or if the file it names is
       not writable.  A shell can  access  the	commands  of  all  interactive
       shells which use the same named HISTFILE.  The built-in command hist is
       used to list or edit a portion of this file.  The portion of  the  file
       to be edited or listed can be selected by number or by giving the first
       character or characters of the command.	A single command or  range  of
       commands	 can be specified.  If you do not specify an editor program as
       an argument to hist then the value of the variable  HISTEDIT  is	 used.
       If  HISTEDIT is unset, the obsolete variable FCEDIT is used.  If FCEDIT
       is not defined, then /bin/ed is used.  The edited command(s) is printed
       and  re-executed	 upon leaving the editor unless you quit without writ-
       ing.  The -s option (and in obsolete versions, the editor  name	-)  is
       used  to skip the editing phase and to re-execute the command.  In this
       case a substitution parameter of the form old=new can be used to modify
       the  command  before  execution.	 For example, with the preset alias r,
       which is aliased to 'hist -s', typing `r bad=good  c'  will  re-execute
       the  most  recent command which starts with the letter c, replacing the
       first occurrence of the string bad with the string good.

   In-line Editing Options.
       Normally, each command line entered from a terminal  device  is	simply
       typed  followed by a new-line (`RETURN' or `LINE FEED').	 If either the
       emacs, gmacs, or vi option is active, the user  can  edit  the  command
       line.   To  be  in  either  of  these  edit modes set the corresponding
       option.	An editing option is  automatically  selected  each  time  the
       VISUAL or EDITOR variable is assigned a value ending in either of these
       option names.

       The editing features require that the user's terminal  accept  `RETURN'
       as  carriage return without line feed and that a space (` ') must over-
       write the current character on the screen.

       Unless the multiline option is on, the editing modes implement  a  con-
       cept  where  the	 user is looking through a window at the current line.
       The window width is the value of COLUMNS if it  is  defined,  otherwise
       80.   If	 the window width is too small to display the prompt and leave
       at least 8 columns to enter input, the prompt  is  truncated  from  the
       left.  If the line is longer than the window width minus two, a mark is
       displayed at the end of the window to notify the user.  As  the	cursor
       moves  and  reaches  the	 window boundaries the window will be centered
       about the cursor.  The mark is a > (<, *) if the line  extends  on  the
       right (left, both) side(s) of the window.

       The  search  commands  in  each edit mode provide access to the history
       file.  Only strings are matched, not patterns, although a leading ^  in
       the  string  restricts the match to begin at the first character in the
       line.

       Each of the edit modes has an operation to list the files  or  commands
       that match a partially entered word.  When applied to the first word on
       the line, or the first word after a ;, |, &, or (, and  the  word  does
       not  begin  with	 ~ or contain a /, the list of aliases, functions, and
       executable commands defined by the PATH variable that could  match  the
       partial word is displayed.  Otherwise, the list of files that match the
       given word is displayed.	 If the partially entered word does  not  con-
       tain  any  file expansion characters, a * is appended before generating
       these lists.  After displaying the generated list, the  input  line  is
       redrawn.	  These	 operations  are  called command name listing and file
       name listing, respectively.  There are additional operations,  referred
       to  as  command name completion and file name completion, which compute
       the list of matching commands or files, but  instead  of	 printing  the
       list,  replace  the current word with a complete or partial match.  For
       file name completion, if the match is unique, a / is  appended  if  the
       file is a directory and a space is appended if the file is not a direc-
       tory.  Otherwise, the longest common prefix for all the matching	 files
       replaces	 the  word.   For command name completion, only the portion of
       the file names after the last / are used to find	 the  longest  command
       prefix.	 If  only  a single name matches this prefix, then the word is
       replaced with the command name followed by a space.  When using	a  tab
       for  completion	that  does  not yield a unique match, a subsequent tab
       will provide a numbered list  of	 matching  alternatives.   A  specific
       selection  can  be  made by entering the selection number followed by a
       tab.

   Key Bindings.
       The KEYBD trap can be used to intercept keys  as	 they  are  typed  and
       change  the  characters that are actually seen by the shell.  This trap
       is executed after each character (or sequence of	 characters  when  the
       first  character is ESC) is entered while reading from a terminal.  The
       variable .sh.edchar contains the character or character sequence	 which
       generated  the  trap.   Changing	 the  value  of .sh.edchar in the trap
       action causes the shell to behave as if the new value were entered from
       the keyboard rather than the original value.

       The  variable .sh.edcol is set to the input column number of the cursor
       at the time of the input.  The variable .sh.edmode is set to  ESC  when
       in  vi  insert  mode  (see below) and is null otherwise.	 By prepending
       ${.sh.editmode} to a value assigned to .sh.edchar  it  will  cause  the
       shell to change to control mode if it is not already in this mode.

       This trap is not invoked for characters entered as arguments to editing
       directives, or while reading input for a character search.

   Emacs Editing Mode.
       This mode is entered by enabling either the emacs or gmacs option.  The
       only  difference between these two modes is the way they handle ^T.  To
       edit, the user moves the cursor to the  point  needing  correction  and
       then inserts or deletes characters or words as needed.  All the editing
       commands are control characters or escape sequences.  The notation  for
       control	characters  is caret (^) followed by the character.  For exam-
       ple, ^F is the notation for control F.  This is entered	by  depressing
       `f'  while  holding  down the `CTRL' (control) key.  The `SHIFT' key is
       not depressed.  (The notation ^?	 indicates the DEL (delete) key.)

       The notation for escape sequences is M- followed by a  character.   For
       example,	 M-f  (pronounced  Meta f) is entered by depressing ESC (ascii
       033) followed by `f'.  (M-F would be the notation for ESC  followed  by
       `SHIFT' (capital) `F'.)

       All  edit  commands operate from any place on the line (not just at the
       beginning).  Neither the `RETURN' nor the `LINE FEED'  key  is  entered
       after edit commands except when noted.

       ^F	 Move cursor forward (right) one character.
       M-[C	 Move cursor forward (right) one character.
       M-f	 Move  cursor forward one word.	 (The emacs editor's idea of a
		 word is a string of characters consisting  of	only  letters,
		 digits and underscores.)
       ^B	 Move cursor backward (left) one character.
       M-[D	 Move cursor backward (left) one character.
       M-b	 Move cursor backward one word.
       ^A	 Move cursor to start of line.
       M-[H	 Move cursor to start of line.
       ^E	 Move cursor to end of line.
       M-[Y	 Move cursor to end of line.
       ^]char	 Move cursor forward to character char on current line.
       M-^]char	 Move cursor backward to character char on current line.
       ^X^X	 Interchange the cursor and mark.
       erase	 (User	defined erase character as defined by the stty(1) com-
		 mand, usually ^H or #.)  Delete previous character.
       lnext	 (User defined	literal	 next  character  as  defined  by  the
		 stty(1)  command.   or	 ^V if not defined.)  Removes the next
		 character's editing features (if any).
       ^D	 Delete current character.
       M-d	 Delete current word.
       M-^H	 (Meta-backspace) Delete previous word.
       M-h	 Delete previous word.
       M-^?	 (Meta-DEL) Delete previous word (if your interrupt  character
		 is ^?	(DEL, the default) then this command will not work).
       ^T	 Transpose  current  character	with  previous	character  and
		 advance the cursor in emacs  mode.   Transpose	 two  previous
		 characters in gmacs mode.
       ^C	 Capitalize current character.
       M-c	 Capitalize current word.
       M-l	 Change the current word to lower case.
       ^K	 Delete	 from  the cursor to the end of the line.  If preceded
		 by a numerical parameter whose value is less than the current
		 cursor	 position,  then  delete from given position up to the
		 cursor.  If preceded by a numerical parameter whose value  is
		 greater  than	the  current cursor position, then delete from
		 cursor up to given cursor position.
       ^W	 Kill from the cursor to the mark.
       M-p	 Push the region from the cursor to the mark on the stack.
       kill	 (User defined kill character as defined by the stty  command,
		 usually ^G or @.)  Kill the entire current line.  If two kill
		 characters are entered in  succession,	 all  kill  characters
		 from  then on cause a line feed (useful when using paper ter-
		 minals).
       ^Y	 Restore last item removed from line. (Yank item back  to  the
		 line.)
       ^L	 Line feed and print current line.
       M-^L	 Clear the screen.
       ^@	 (Null character) Set mark.
       M-space	 (Meta space) Set mark.
       ^J	 (New line) Execute the current line.
       ^M	 (Return) Execute the current line.
       eof	 End-of-file  character,  normally ^D, is processed as an End-
		 of-file only if the current line is null.
       ^P	 Fetch previous command.  Each time ^P is entered the previous
		 command  back	in time is accessed.  Moves back one line when
		 not on the first line of a multi-line command.
       M-[A	 Equivalent to ^P.
       M-<	 Fetch the least recent (oldest) history line.
       M->	 Fetch the most recent (youngest) history line.
       ^N	 Fetch next command line.  Each time ^N is  entered  the  next
		 command line forward in time is accessed.
       M-[B	 Equivalent to ^N.
       ^Rstring	 Reverse search history for a previous command line containing
		 string.  If a parameter of zero is given, the search is  for-
		 ward.	 String is terminated by a `RETURN' or `NEW LINE'.  If
		 string is preceded by a ^, the matched line must  begin  with
		 string.   If  string  is  omitted, then the next command line
		 containing the most recent string is accessed.	 In this  case
		 a parameter of zero reverses the direction of the search.
       ^O	 Operate  -  Execute  the current line and fetch the next line
		 relative to current line from the history file.
       M-digits	 (Escape) Define numeric parameter, the digits are taken as  a
		 parameter  to	the  next command.  The commands that accept a
		 parameter are ^F, ^B, erase, ^C, ^D, ^K, ^R, ^P, ^N, ^], M-.,
		 M-^], M-_, M-=, M-b, M-c, M-d, M-f, M-h, M-l and M-^H.
       M-letter	 Soft-key  -  Your  alias list is searched for an alias by the
		 name _letter and if an alias of this  name  is	 defined,  its
		 value	will  be inserted on the input queue.  The letter must
		 not be one of the above meta-functions.
       M-[letter Soft-key - Your alias list is searched for an	alias  by  the
		 name  __letter	 and  if an alias of this name is defined, its
		 value will be inserted on the input queue.  The can  be  used
		 to program functions keys on many terminals.
       M-.	 The  last  word  of  the  previous command is inserted on the
		 line.	If preceded by a numeric parameter, the value of  this
		 parameter  determines	which  word  to insert rather than the
		 last word.
       M-_	 Same as M-..
       M-*	 Attempt file name generation on the current word.  An	aster-
		 isk is appended if the word doesn't match any file or contain
		 any special pattern characters.
       M-ESC	 Command or file name completion as described above.
       ^I tab	 Attempts command or file name completion as described	above.
		 If a partial completion occurs, repeating this will behave as
		 if M-= were entered.  If no match is found or	entered	 after
		 space, a tab is inserted.
       M-=	 If not preceded by a numeric parameter, it generates the list
		 of matching commands or file names as described above.	  Oth-
		 erwise,  the  word  under  the cursor is replaced by the item
		 corresponding to the value of the numeric parameter from  the
		 most  recently generated command or file list.	 If the cursor
		 is not on a word, it is inserted instead.
       ^U	 Multiply parameter of next command by 4.
       \	 Escape next character.	 Editing characters, the user's erase,
		 kill  and  interrupt (normally ^?)  characters may be entered
		 in a command line or in a search string if preceded by	 a  \.
		 The \ removes the next character's editing features (if any).
       M-^V	 Display version of the shell.
       M-#	 If the line does not begin with a #, a # is inserted  at  the
		 beginning  of	the line and after each new-line, and the line
		 is entered.  This causes a comment to be inserted in the his-
		 tory file.  If the line begins with a #, the # is deleted and
		 one # after each new-line is also deleted.

   Vi Editing Mode.
       There are two typing modes.  Initially, when you enter  a  command  you
       are in the input mode.  To edit, the user enters control mode by typing
       ESC (033) and moves the cursor to the point needing correction and then
       inserts	or  deletes  characters or words as needed.  Most control com-
       mands accept an optional repeat count prior to the command.

       When in vi mode on most	systems,  canonical  processing	 is  initially
       enabled	and the command will be echoed again if the speed is 1200 baud
       or greater and it contains any control characters or less than one sec-
       ond has elapsed since the prompt was printed.  The ESC character termi-
       nates canonical processing for the remainder of	the  command  and  the
       user  can then modify the command line.	This scheme has the advantages
       of canonical processing with the type-ahead echoing of raw mode.

       If the option viraw is also set, the terminal will always have  canoni-
       cal processing disabled.	 This mode is implicit for systems that do not
       support two alternate end of line delimiters, and may  be  helpful  for
       certain terminals.

	Input Edit Commands
	      By default the editor is in input mode.
	      erase	(User  defined	erase character as defined by the stty
			command, usually ^H or #.)  Delete previous character.
	      ^W	Delete	the  previous  blank  separated word.  On some
			systems the viraw option may be required for  this  to
			work.
	      eof	As the first character of the line causes the shell to
			terminate unless the ignoreeof option is set.	Other-
			wise this character is ignored.
	      lnext	(User defined literal next character as defined by the
			stty(1) or ^V if not defined.)	Removes the next char-
			acter's	 editing  features  (if any).  On some systems
			the viraw option may be required for this to work.
	      \		Escape the next erase or kill character.
	      ^I tab	Attempts command or file name completion as  described
			above and returns to input mode.  If a partial comple-
			tion occurs, repeating this will behave as if  =  were
			entered	 from  control	mode.  If no match is found or
			entered after space, a tab is inserted.
	Motion Edit Commands
	      These commands will move the cursor.
	      [count]l	Cursor forward (right) one character.
	      [count][C Cursor forward (right) one character.
	      [count]w	Cursor forward one alpha-numeric word.
	      [count]W	Cursor to the beginning of the next word that  follows
			a blank.
	      [count]e	Cursor to end of word.
	      [count]E	Cursor to end of the current blank delimited word.
	      [count]h	Cursor backward (left) one character.
	      [count][D Cursor backward (left) one character.
	      [count]b	Cursor backward one word.
	      [count]B	Cursor to preceding blank separated word.
	      [count]|	Cursor to column count.
	      [count]fc Find the next character c in the current line.
	      [count]Fc Find the previous character c in the current line.
	      [count]tc Equivalent to f followed by h.
	      [count]Tc Equivalent to F followed by l.
	      [count];	Repeats	 count	times,	the last single character find
			command, f, F, t, or T.
	      [count],	Reverses the last single character find command	 count
			times.
	      0		Cursor to start of line.
	      ^		Cursor to start of line.
	      [H	Cursor to first non-blank character in line.
	      $		Cursor to end of line.
	      [Y	Cursor to end of line.
	      %		Moves  to balancing (, ), {, }, [, or ].  If cursor is
			not on one of the above characters, the	 remainder  of
			the  line  is searched for the first occurrence of one
			of the above characters first.
	Search Edit Commands
	      These commands access your command history.
	      [count]k	Fetch previous command.	 Each time k  is  entered  the
			previous command back in time is accessed.
	      [count]-	Equivalent to k.
	      [count][A Equivalent to k.
	      [count]j	Fetch  next  command.  Each time j is entered the next
			command forward in time is accessed.
	      [count]+	Equivalent to j.
	      [count][B Equivalent to j.
	      [count]G	The command number count is fetched.  The  default  is
			the least recent history command.
	      /string	Search backward through history for a previous command
			containing string.  String is terminated by a `RETURN'
			or  `NEW LINE'.	  If  string  is  preceded by a ^, the
			matched line must begin with  string.	If  string  is
			null, the previous string will be used.
	      ?string	Same  as  /  except that search will be in the forward
			direction.
	      n		Search for next match of the last pattern to  /	 or  ?
			commands.
	      N		Search	for  next match of the last pattern to / or ?,
			but in reverse direction.
	Text Modification Edit Commands
	      These commands will modify the line.
	      a		Enter input mode and  enter  text  after  the  current
			character.
	      A		Append text to the end of the line.  Equivalent to $a.
	      [count]cmotion
	      c[count]motion
			Delete current character through  the  character  that
			motion	would move the cursor to and enter input mode.
			If motion is c, the entire line will  be  deleted  and
			input mode entered.
	      C		Delete	the  current character through the end of line
			and enter input mode.  Equivalent to c$.
	      S		Equivalent to cc.
	      [count]s	Replace characters under the cursor in input mode.
	      D		Delete the current character through the end of	 line.
			Equivalent to d$.
	      [count]dmotion
	      d[count]motion
			Delete	current	 character  through the character that
			motion would move to.  If motion is  d	,  the	entire
			line will be deleted.
	      i		Enter  input  mode  and insert text before the current
			character.
	      I		Insert text before the beginning of the line.  Equiva-
			lent to 0i.
	      [count]P	Place  the  previous text modification before the cur-
			sor.
	      [count]p	Place the previous text modification after the cursor.
	      R		Enter  input mode and replace characters on the screen
			with characters you type overlay fashion.
	      [count]rc Replace the count character(s) starting at the current
			cursor position with c, and advance the cursor.
	      [count]x	Delete current character.
	      [count]X	Delete preceding character.
	      [count].	Repeat the previous text modification command.
	      [count]~	Invert	the case of the count character(s) starting at
			the current cursor position and advance the cursor.
	      [count]_	Causes the count word of the previous  command	to  be
			appended  and  input  mode  entered.  The last word is
			used if count is omitted.
	      *		Causes an * to be appended to  the  current  word  and
			file name generation attempted.	 If no match is found,
			it rings the bell.  Otherwise, the word is replaced by
			the matching pattern and input mode is entered.
	      \		Command or file name completion as described above.
	Other Edit Commands
	      Miscellaneous commands.
	      [count]ymotion
	      y[count]motion
			Yank  current  character through character that motion
			would move the cursor to and puts them into the delete
			buffer.	 The text and cursor are unchanged.
	      yy	Yanks the entire line.
	      Y		Yanks  from  current position to end of line.  Equiva-
			lent to y$.
	      u		Undo the last text modifying command.
	      U		Undo all the text modifying commands performed on  the
			line.
	      [count]v	Returns	 the  command hist -e ${VISUAL:-${EDITOR:-vi}}
			count in the input buffer.  If count is omitted,  then
			the current line is used.
	      ^L	Line  feed and print current line.  Has effect only in
			control mode.
	      ^J	(New line) Execute the	current	 line,	regardless  of
			mode.
	      ^M	(Return) Execute the current line, regardless of mode.
	      #		If the first character of the command  is  a  #,  then
			this  command deletes this # and each # that follows a
			newline.  Otherwise, sends the line after inserting  a
			#  in  front  of each line in the command.  Useful for
			causing the current line to be inserted in the history
			as  a  comment	and  uncommenting previously commented
			commands in the history file.
	      [count]=	If count is not specified, it generates	 the  list  of
			matching  commands  or	file names as described above.
			Otherwise, the word under the the cursor  is  replaced
			by  the	 count	item  from the most recently generated
			command or file list.  If the cursor is not on a word,
			it is inserted instead.
	      @letter	Your  alias  list is searched for an alias by the name
			_letter and if an alias of this name is	 defined,  its
			value will be inserted on the input queue for process-
			ing.
	      ^V	Display version of the shell.

   Built-in Commands.
       The following  simple-commands  are  executed  in  the  shell  process.
       Input/Output redirection is permitted.  Unless otherwise indicated, the
       output is written on file descriptor 1 and the exit status, when	 there
       is  no syntax error, is zero.  Except for :, true, false, echo, newgrp,
       and login, all built-in commands accept -- to indicate end of  options.
       They  also  interpret  the option --man as a request to display the man
       page onto standard error and -?	as a help request which prints a usage
       message	on  standard  error.  Commands that are preceded by one or two
       symbols are special built-in commands and are treated specially in  the
       following ways:
       1.     Variable assignment lists preceding the command remain in effect
	      when the command completes.
       2.     I/O redirections are processed after variable assignments.
       3.     Errors cause a script that contains them to abort.
       4.     They are not valid function names.
       5.     Words following a command preceded by that are in the format  of
	      a	 variable  assignment  are  expanded  with the same rules as a
	      variable assignment.  This means that tilde substitution is per-
	      formed after the = sign and field splitting and file name gener-
	      ation are not performed.

	: [ arg ... ]
	      The command only expands parameters.

	. name [ arg ... ]
	      If name is a function defined with the  function	name  reserved
	      word syntax, the function is executed in the current environment
	      (as if it had been defined with the name()  syntax.)   Otherwise
	      if  name	refers to a file, the file is read in its entirety and
	      the commands are executed in the current shell environment.  The
	      search path specified by PATH is used to find the directory con-
	      taining the file.	 If any arguments arg are given,  they	become
	      the  positional  parameters  while processing the .  command and
	      the original positional parameters are restored upon completion.
	      Otherwise	 the  positional  parameters  are unchanged.  The exit
	      status is the exit status of the last command executed.

	alias [ -ptx ]	[ name[ =value	] ] ...
	      alias with no arguments prints the list of aliases in  the  form
	      name=value  on  standard	output.	 The -p option causes the word
	      alias to be inserted before each one.  When one  or  more	 argu-
	      ments  are  given, an alias is defined for each name whose value
	      is given.	 A trailing space in value causes the next word to  be
	      checked  for alias substitution.	The obsolete -t option is used
	      to set and list tracked aliases.	The value of a	tracked	 alias
	      is the full pathname corresponding to the given name.  The value
	      becomes undefined when the value of PATH is reset but the	 alias
	      remains  tracked.	  Without  the -t option, for each name in the
	      argument list for which no value is given, the name and value of
	      the  alias  is  printed.	 The obsolete -x option has no effect.
	      The exit status is non-zero if a name is given,  but  no	value,
	      and no alias has been defined for the name.

       bg [ job... ]
	      This  command is only on systems that support job control.  Puts
	      each specified job into the background.  The current job is  put
	      in  the  background  if  job  is	not specified.	See Jobs for a
	      description of the format of job.

	break [ n ]
	      Exit from the enclosing for, while, until, or  select  loop,  if
	      any.  If n is specified, then break n levels.

       builtin [ -ds ] [ -f file ] [ name ... ]
	      If  name	is  not	 specified, and no -f option is specified, the
	      built-ins are printed on standard output.	 The -s option	prints
	      only the special built-ins.  Otherwise, each name represents the
	      pathname whose basename is the name of the built-in.  The	 entry
	      point function name is determined by prepending b_ to the built-
	      in name.	The ISO C/C++ prototype is b_mycommand(int argc,  char
	      *argv[],	void *context) for the builtin command mycommand where
	      argv is array an of argc elements and  context  is  an  optional
	      pointer to a Shell_t structure as described in <ast/shell.h>.
	      Special built-ins cannot be bound to a pathname or deleted.  The
	      -d option deletes each of the given built-ins.  On systems  that
	      support  dynamic	loading,  the -f option names a shared library
	      containing the code for built-ins.  The  shared  library	prefix
	      and/or suffix, which depend on the system, can be omitted.  Once
	      a library is loaded, its symbols become available for subsequent
	      invocations  of  builtin.	  Multiple  libraries can be specified
	      with separate invocations of the builtin command.	 Libraries are
	      searched in the reverse order in which they are specified.  When
	      a library is loaded, it looks for	 a  function  in  the  library
	      whose name is lib_init() and invokes this function with an argu-
	      ment of 0.

       cd [ -LP ] [ arg ]
       cd [ -LP ] old new
	      This command can be in either of two forms.  In the  first  form
	      it changes the current directory to arg.	If arg is - the direc-
	      tory is changed to the previous directory.  The  shell  variable
	      HOME is the default arg.	The variable PWD is set to the current
	      directory.  The shell variable CDPATH defines  the  search  path
	      for  the	directory containing arg.  Alternative directory names
	      are separated by a colon (:).  The default path is <null> (spec-
	      ifying  the current directory).  Note that the current directory
	      is specified by a null path name, which can  appear  immediately
	      after  the  equal	 sign or between the colon delimiters anywhere
	      else in the path list.  If arg begins with a / then  the	search
	      path  is	not  used.   Otherwise,	 each directory in the path is
	      searched for arg.
	      The second form of cd substitutes the string new for the	string
	      old  in  the current directory name, PWD, and tries to change to
	      this new directory.
	      By default, symbolic link names are treated literally when find-
	      ing  the	directory  name.  This is equivalent to the -L option.
	      The -P option causes symbolic links to be resolved  when	deter-
	      mining the directory.  The last instance of -L or -P on the com-
	      mand line determines which method is used.
	      The cd command may not be executed by rksh.  rksh93.

       command [ -pvxV ] name [ arg ... ]
	      Without the -v or -V options, command  executes  name  with  the
	      arguments	 given by arg.	The -p option causes a default path to
	      be searched rather than the one defined by the  value  of	 PATH.
	      Functions	 will not be searched for when finding name.  In addi-
	      tion, if name refers to a special built-in, none of the  special
	      properties  associated with the leading daggers will be honored.
	      (For example, the predefined alias redirect='command exec'  pre-
	      vents  a	script from terminating when an invalid redirection is
	      given.)  With the -x option, if command execution	 would	result
	      in  a failure because there are too many arguments, errno E2BIG,
	      the shell will invoke command name multiple times with a	subset
	      of the arguments on each invocation.  Arguments that occur prior
	      to the first word that expands to multiple arguments  and	 after
	      the  last word that expands to multiple arguments will be passed
	      on each invocation.  The exit status will be the maximum invoca-
	      tion  exit status.  With the -v option, command is equivalent to
	      the built-in whence command  described  below.   The  -V	option
	      causes command to act like whence -v.

	continue [ n ]
	      Resume the next iteration of the enclosing for, while, until, or
	      select loop.  If n is specified, then resume at the n-th enclos-
	      ing loop.

       disown [ job... ]
	      Causes  the shell not to send a HUP signal to each given job, or
	      all active jobs if job is omitted, when  a  login	 shell	termi-
	      nates.

       echo [ arg ... ]
	      When  the	 first	arg  does  not begin with a -, and none of the
	      arguments contain a \, then echo prints each  of	its  arguments
	      separated	 by  a space and terminated by a new-line.  Otherwise,
	      the behavior of echo is system dependent	and  print  or	printf
	      described	 below	should	be  used.   See	 echo(1) for usage and
	      description.

	eval [ arg ... ]
	      The arguments are read as input to the shell and	the  resulting
	      command(s) executed.

	exec [ -c ] [ -a name ] [ arg ... ]
	      If  arg is given, the command specified by the arguments is exe-
	      cuted in place of this shell without  creating  a	 new  process.
	      The -c option causes the environment to be cleared before apply-
	      ing variable assignments associated with	the  exec  invocation.
	      The  -a  option causes name rather than the first arg, to become
	      argv[0] for the new process.  Input/output arguments may	appear
	      and affect the current process.  If arg is not given, the effect
	      of this command is to modify file descriptors as	prescribed  by
	      the  input/output	 redirection  list.   In  this	case, any file
	      descriptor numbers greater than 2	 that  are  opened  with  this
	      mechanism are closed when invoking another program.

	exit [ n ]
	      Causes  the  shell  to exit with the exit status specified by n.
	      The value will be the least significant 8 bits of the  specified
	      status.	If  n  is omitted, then the exit status is that of the
	      last command executed.  An end-of-file will also cause the shell
	      to  exit	except for a shell which has the ignoreeof option (see
	      set below) turned on.

	export [ -p ] [ name[=value] ] ...
	      If name is not given, the names and values of each variable with
	      the  export  attribute  are  printed with the values quoted in a
	      manner that allows them to be re-input.  The  -p	option	causes
	      the  word export to be inserted before each one.	Otherwise, the
	      given names are marked for automatic export to  the  environment
	      of subsequently-executed commands.

       false  Does nothing, and exits 1. Used with until for infinite loops.

       fg [ job... ]
	      This  command is only on systems that support job control.  Each
	      job specified is brought to the foreground and waited for in the
	      specified order.	Otherwise, the current job is brought into the
	      foreground.  See Jobs for a description of the format of job.

       getconf [ name [ pathname ] ]
	      Prints the current value of the configuration parameter given by
	      name.   The  configuration  parameters  are  defined by the IEEE
	      POSIX 1003.1 and IEEE POSIX 1003.2 standards.  (See  pathconf(2)
	      and  sysconf(2).)	 The pathname argument is required for parame-
	      ters whose value depends on the location in the file system.  If
	      no  arguments  are given, getconf prints the names and values of
	      the current configuration parameters.  The pathname  /  is  used
	      for each of the parameters that requires pathname.

       getopts [  -a name ] optstring vname [ arg ... ]
	      Checks arg for legal options.  If arg is omitted, the positional
	      parameters are used.  An option argument begins with a + or a -.
	      An  option not beginning with + or - or the argument -- ends the
	      options.	Options beginning with + are only recognized when opt-
	      string  begins  with  a  +.  optstring contains the letters that
	      getopts recognizes.  If a letter is followed by a :, that option
	      is  expected  to have an argument.  The options can be separated
	      from the argument by blanks.  The option -?  causes  getopts  to
	      generate a usage message on standard error.  The -a argument can
	      be used to specify the name to use for the usage message,	 which
	      defaults to $0.
	      getopts  places  the next option letter it finds inside variable
	      vname each time it  is  invoked.	 The  option  letter  will  be
	      prepended	 with  a + when arg begins with a +.  The index of the
	      next arg is stored in OPTIND.  The option argument, if any, gets
	      stored in OPTARG.
	      A	 leading  : in optstring causes getopts to store the letter of
	      an invalid option in OPTARG, and to  set	vname  to  ?   for  an
	      unknown option and to : when a required option argument is miss-
	      ing.  Otherwise, getopts prints an error message.	 The exit sta-
	      tus is non-zero when there are no more options.
	      There is no way to specify any of the options :, +, -, ?, [, and
	      ].  The option # can only be specified as the first option.

       hist [ -e ename	] [ -nlr ] [ first [ last ] ]
       hist -s	[ old=new ] [ command ]
	      In the first form, a range of commands from  first  to  last  is
	      selected	from the last HISTSIZE commands that were typed at the
	      terminal.	 The arguments first and last may be  specified	 as  a
	      number  or  as  a	 string.   A string is used to locate the most
	      recent command starting with the given string.  A negative  num-
	      ber  is used as an offset to the current command number.	If the
	      -l option is selected, the commands are listed on standard  out-
	      put.   Otherwise,	 the editor program ename is invoked on a file
	      containing these keyboard commands.  If ename is	not  supplied,
	      then the value of the variable HISTEDIT is used.	If HISTEDIT is
	      not set, then FCEDIT (default /bin/ed) is used  as  the  editor.
	      When  editing  is complete, the edited command(s) is executed if
	      the changes have been saved.  If last is not specified, then  it
	      will be set to first.  If first is not specified, the default is
	      the previous command for	editing	 and  -16  for	listing.   The
	      option  -r  reverses the order of the commands and the option -n
	      suppresses command numbers when listing.	In  the	 second	 form,
	      command  is interpreted as first described above and defaults to
	      the last command executed.  The resulting	 command  is  executed
	      after the optional substitution old=new is performed.

       jobs [ -lnp ] [ job ... ]
	      Lists  information  about	 each given job; or all active jobs if
	      job is omitted.  The -l option lists process ids in addition  to
	      the  normal  information.	 The -n option only displays jobs that
	      have stopped or exited  since  last  notified.   The  -p	option
	      causes  only  the	 process  group	 to be listed.	See Jobs for a
	      description of the format of job.

       kill [ -s signame ] job ...
       kill [ -n signum ] job ...
       kill -l [ sig ... ]
	      Sends either the TERM (terminate) signal or the specified signal
	      to the specified jobs or processes.  Signals are either given by
	      number with the -n option or by name  with  the  -s  option  (as
	      given  in	 <signal.h>,  stripped	of the prefix ``SIG'' with the
	      exception that SIGCLD is named CHLD).  For backward  compatibil-
	      ity,  the	 n  and s can be omitted and the number or name placed
	      immediately after the -.	If the signal being sent is TERM (ter-
	      minate)  or HUP (hangup), then the job or process will be sent a
	      CONT (continue) signal if it is stopped.	The argument  job  can
	      be  the  process	id of a process that is not a member of one of
	      the active jobs.	See Jobs for a description of  the  format  of
	      job.   In	 the third form, kill -l, if sig is not specified, the
	      signal names are listed.	Otherwise, for	each  sig  that	 is  a
	      name,  the  corresponding signal number is listed.  For each sig
	      that is a number, the signal name	 corresponding	to  the	 least
	      significant 8 bits of sig is listed.

       let arg ...
	      Each  arg	 is  a separate arithmetic expression to be evaluated.
	      See Arithmetic Evaluation above, for a description of arithmetic
	      expression evaluation.
	      The exit status is 0 if the value of the last expression is non-
	      zero, and 1 otherwise.

	newgrp [ arg ... ]
	      Equivalent to exec /bin/newgrp arg ....

       print [ -Renprs ] [ -u unit] [ -f format ] [ arg ... ]
	      With no options or with option - or --, each arg is  printed  on
	      standard	output.	  The  -f  option  causes  the arguments to be
	      printed as described by printf.  In this case, any e,  n,	 r,  R
	      options are ignored.  Otherwise, unless the -R or -r, are speci-
	      fied, the following escape conventions will be applied:
	      \a     The alert character (ascii 07).
	      \b     The backspace character (ascii 010).
	      \c     Causes print to end without processing more arguments and
		     not adding a new-line.
	      \f     The formfeed character (ascii 014).
	      \n     The new-line character (ascii 012).
	      \r     The carriage return character (ascii 015).
	      \t     The tab character (ascii 011).
	      \v     The vertical tab character (ascii 013).
	      \E     The escape character (ascii 033).
	      \\     The backslash character \.
	      \0x    The  character  defined  by  the  1,  2, or 3-digit octal
		     string given by x.

	      The -R option will print all subsequent  arguments  and  options
	      other than -n.  The -e causes the above escape conventions to be
	      applied This is the default behavior.  It reverses the effect of
	      an earlier -r.  The -p option causes the arguments to be written
	      onto the pipe of the process spawned with |& instead of standard
	      output.	The  -s option causes the arguments to be written onto
	      the history file instead of standard output.  The -u option  can
	      be  used to specify a one digit file descriptor unit number unit
	      on which the output will be placed.  The default is 1.   If  the
	      option -n is used, no new-line is added to the output.

       printf format [ arg ... ]
	      The  arguments  arg are printed on standard output in accordance
	      with the ANSI-C formatting  rules	 associated  with  the	format
	      string format.  If the number of arguments exceeds the number of
	      format specifications, the format string	is  reused  to	format
	      remaining arguments.  The following extensions can also be used:
	      A %b format can be used instead of %s to cause escape  sequences
	      in  the  corresponding arg to be expanded as described in print.
	      A %B option causes each of the arguments to be treated as	 vari-
	      able  names  and	the  binary value of variable will be printed.
	      This is most useful for variables whose attribute is -b.	 A  %H
	      format can be used instead of %s to cause characters in arg that
	      are special in HTML and XML to be output to be output  as	 their
	      entity name.  A %P format can be used instead of %s to cause arg
	      to be interpreted as  an	extended  regular  expression  and  be
	      printed  as a shell pattern.  A %R format can be used instead of
	      %s to cause arg interpreted as a shell pattern and to be printed
	      as  an  extended	regular	 expression.   A %q format can be used
	      instead of %s to cause the resulting string to be	 quoted	 in  a
	      manner than can be reinput to the shell.	A %(date-format)T for-
	      mat can be use to treat an argument as a date/time string and to
	      format the date/time according to the date-format as defined for
	      the date(1) command.  A %Z format will output a byte whose value
	      is 0.  The precision field of the %d format can be followed by a
	      .	 and the output base.  In this	case,  the  #  flag  character
	      caues  base#  to	be prepended.  The # flag when used with the d
	      specifier without an output base, causes the output to  be  dis-
	      played  in  thousands units with one of the suffixes k M G T P E
	      to indicate the unit.  The # flag when used with the i specifier
	      causes  the  output to be displayed in 1024 with one of the suf-
	      fixes Ki Mi Gi Ti Pi Ei to indicate the unit.  The  =  flag  has
	      been  added  to  center  the  output  within the specified field
	      width.

       pwd [ -LP ]
	      Outputs the value of the	current	 working  directory.   The  -L
	      option is the default; it prints the logical name of the current
	      directory.  If the -P option is given, all  symbolic  links  are
	      resolved	from  the  name.  The last instance of -L or -P on the
	      command line determines which method is used.

       read [ -Aprs ] [ -d delim] [ -n n] [ [ -N n] [ [ -t timeout] [ -u unit]
       [ vname?prompt ] [ vname ... ]
	      The shell input mechanism.  One line is read and	is  broken  up
	      into  fields  using  the	characters  in IFS as separators.  The
	      escape character, \, is used to remove any special  meaning  for
	      the  next	 character  and	 for line continuation.	 The -d option
	      causes the read to continue to  the  first  character  of	 delim
	      rather  than  new-line.  The -n option causes at most n bytes to
	      read rather a full line but will return when reading from a slow
	      device  as soon as any characters have been read.	 The -N option
	      causes exactly n to be  read  unless  an	end-of-file  has  been
	      encountered  or the read times out because of the -t option.  In
	      raw mode, -r, the \ character is	not  treated  specially.   The
	      first  field is assigned to the first vname, the second field to
	      the second vname, etc., with leftover  fields  assigned  to  the
	      last vname.  When vname has the binary attribute and -n or -N is
	      specified, the bytes that are read are stored directly into  the
	      variable.	  If  the -v is specified, then the value of the first
	      vname will be used as a default value when reading from a termi-
	      nal device.  The -A option causes the variable vname to be unset
	      and each field that is read to be stored in successive  elements
	      of the indexed array vname.  The -p option causes the input line
	      to be taken from the input pipe of  a  process  spawned  by  the
	      shell  using |&.	If the -s option is present, the input will be
	      saved as a command in the history file.  The option  -u  can  be
	      used  to	specify	 a one digit file descriptor unit unit to read
	      from.  The file descriptor can be opened with the	 exec  special
	      built-in command.	 The default value of unit n is 0.  The option
	      -t is used to specify a timeout in seconds when reading  from  a
	      terminal	or  pipe.   If vname is omitted, then REPLY is used as
	      the default vname.  An end-of-file with  the  -p	option	causes
	      cleanup for this process so that another can be spawned.	If the
	      first argument contains a ?, the remainder of this word is  used
	      as  a  prompt  on	 standard error when the shell is interactive.
	      The exit status is 0 unless an  end-of-file  is  encountered  or
	      read has timed out.

	readonly [ -p ] [ vname[=value] ] ...
	      If  vname	 is  not  given, the names and values of each variable
	      with the readonly attribute is printed with the values quoted in
	      a	 manner	 that  allows  them  to be re-inputted.	 The -p option
	      causes the word readonly to be inserted before each one.	Other-
	      wise,  the given vnames are marked readonly and these names can-
	      not be changed by subsequent assignment.

	return [ n ]
	      Causes a shell function or .  script to return to	 the  invoking
	      script  with  the exit status specified by n.  The value will be
	      the least significant 8 bits of the specified status.  If	 n  is
	      omitted, then the return status is that of the last command exe-
	      cuted.  If return is invoked while not in	 a  function  or  a  .
	      script, then it behaves the same as exit.

	 set  [ +-CGabefhkmnoprstuvx ] [ +-o [ option ] ] ... [ +-A vname ]  [
       arg ... ]
	      The options for this command have meaning as follows:
	      -A      Array  assignment.   Unset the variable vname and assign
		      values sequentially from the arg list.  If +A  is	 used,
		      the variable vname is not unset first.
	      -B      Enable  brace  pattern  field  generation.   This is the
		      default behavior.
	      -C      Prevents redirection > from truncating  existing	files.
		      Files  that are created are opened with the O_EXCL mode.
		      Requires >| to truncate a file when turned on.
	      -G      Causes the pattern ** by itself to match files and  zero
		      or  more	directories  and sub-directories when used for
		      file name generation.  If followed by a / only  directo-
		      ries and sub-directories are matched.
	      -a      All  subsequent variables that are defined are automati-
		      cally exported.
	      -b      Prints job completion messages as soon as	 a  background
		      job  changes  state  rather  than	 waiting  for the next
		      prompt.
	      -e      If a command has a non-zero exit status, execute the ERR
		      trap,  if	 set,  and  exit.  This mode is disabled while
		      reading profiles.
	      -f      Disables file name generation.
	      -h      Each command becomes a tracked alias when first  encoun-
		      tered.
	      -k      (Obsolete). All variable assignment arguments are placed
		      in the environment for a command, not  just  those  that
		      precede the command name.
	      -m      Background jobs will run in a separate process group and
		      a line will print upon completion.  The exit  status  of
		      background jobs is reported in a completion message.  On
		      systems with job control, this option is turned on auto-
		      matically for interactive shells.
	      -n      Read  commands  and check them for syntax errors, but do
		      not execute them.	 Ignored for interactive shells.
	      -o      The following argument  can  be  one  of	the  following
		      option names:
		      allexport
			      Same as -a.
		      errexit Same as -e.
		      bgnice  All background jobs are run at a lower priority.
			      This is the default mode.
		      bracexpand
			      Sans as -B.
		      emacs   Puts you in an emacs style  in-line  editor  for
			      command entry.
		      globstar
			      Same as -G.
		      gmacs   Puts  you	 in  a	gmacs style in-line editor for
			      command entry.
		      ignoreeof
			      The shell will not  exit	on  end-of-file.   The
			      command exit must be used.
		      keyword Same as -k.
		      markdirs
			      All  directory  names  resulting	from file name
			      generation have a trailing / appended.
		      monitor Same as -m.
		      multiline
			      The built-in editors will use multiple lines  on
			      the  screen  for	lines that are longer than the
			      width of the screen.  This may not work for  all
			      terminals.
		      noclobber
			      Same as -C.
		      noexec  Same as -n.
		      noglob  Same as -f.
		      nolog   Do  not save function definitions in the history
			      file.
		      notify  Same as -b.
		      nounset Same as -u.
		      pipefail
			      A pipeline will not complete  until  all	compo-
			      nents  of	 the  pipeline have completed, and the
			      return value will be the value of the last  non-
			      zero  command  to fail or zero of no command has
			      failed.
		      showme  When enabled, simple commands or pipelines  pre-
			      ceded by a semicolon (;) will be displayed as if
			      the xtrace option were enabled but will  not  be
			      executed.	  Otherwise,  the  leading  ;  will be
			      ignored.
		      privileged
			      Same as -p.
		      verbose Same as -v.
		      trackall
			      Same as -h.
		      vi      Puts you in insert mode of a  vi	style  in-line
			      editor  until  you hit the escape character 033.
			      This puts you in control mode.  A	 return	 sends
			      the line.
		      viraw   Each character is processed as it is typed in vi
			      mode.
		      xtrace  Same as -x.
		      If no option name is supplied, then the  current	option
		      settings are printed.
	      -p      Disables	processing of the $HOME/.profile file and uses
		      the file /etc/suid_profile  instead  of  the  ENV	 file.
		      This  mode is on whenever the effective uid (gid) is not
		      equal to the real uid (gid).  Turning  this  off	causes
		      the  effective uid and gid to be set to the real uid and
		      gid.
	      -r      Enables the restricted shell.   This  option  cannot  be
		      unset once set.
	      -s      Sort the positional parameters lexicographically.
	      -t      (Obsolete).   Exit  after reading and executing one com-
		      mand.
	      -u      Treat unset parameters as an error when substituting.
	      -v      Print shell input lines as they are read.
	      -x      Print commands and their arguments as they are executed.
	      --      Do  not  change any of the options; useful in setting $1
		      to a value beginning with -.   If	 no  arguments	follow
		      this option then the positional parameters are unset.

	      As an obsolete feature, if the first arg is - then the -x and -v
	      options are turned off and the next arg is treated as the	 first
	      argument.	  Using	 +  rather  than  - causes these options to be
	      turned off.  These options can also be used upon	invocation  of
	      the  shell.   The	 current  set  of  options may be found in $-.
	      Unless -A is specified, the remaining arguments  are  positional
	      parameters  and  are  assigned,  in  order, to $1 $2 ....	 If no
	      arguments are given, then the names and values of all  variables
	      are printed on the standard output.

	shift [ n ]
	      The  positional  parameters  from $n+1 ...  are renamed $1 ... ,
	      default n is 1.  The parameter n can be any  arithmetic  expres-
	      sion  that evaluates to a non-negative number less than or equal
	      to $#.

       sleep seconds
	      Suspends execution for the number of decimal  seconds  or	 frac-
	      tions of a second given by seconds.

	trap [ -p ] [ action ] [ sig ] ...
	      The  -p  option causes the trap action associated with each trap
	      as specified by the arguments to	be  printed  with  appropriate
	      quoting.	 Otherwise,  action will be processed as if it were an
	      argument to eval when the shell receives	signal(s)  sig.	  Each
	      sig can be given as a number or as the name of the signal.  Trap
	      commands are executed in order of signal number.	Any attempt to
	      set  a trap on a signal that was ignored on entry to the current
	      shell is ineffective.  If action is omitted and the first sig is
	      a	 number,  or if action is -, then the trap(s) for each sig are
	      reset to their original values.  If action is  the  null	string
	      then  this signal is ignored by the shell and by the commands it
	      invokes.	If sig is ERR then action will be executed whenever  a
	      command has a non-zero exit status.  If sig is DEBUG then action
	      will be executed before each command.  The variable  .sh.command
	      will  contain  the  contents  of	the  current command line when
	      action is running.  If sig is 0 or EXIT and the  trap  statement
	      is executed inside the body of a function defined with the func-
	      tion name syntax, then the command action is executed after  the
	      function	completes.  If sig is 0 or EXIT for a trap set outside
	      any function then the command action is executed	on  exit  from
	      the  shell.  If sig is KEYBD, then action will be executed when-
	      ever a key is read while in emacs, gmacs, or vi mode.  The  trap
	      command  with  no arguments prints a list of commands associated
	      with each signal number.

       true   Does nothing, and exits 0. Used with while for infinite loops.

	typeset [ +-AHflabnprtux ] [ +-EFLRZi[n] ]  [ vname[=value ]  ] ...
	      Sets attributes and values for shell  variables  and  functions.
	      When  invoked  inside  a function defined with the function name
	      syntax, a new instance of the variable vname is created, and the
	      variable's  value	 and  type are restored when the function com-
	      pletes.  The following list of attributes may be specified:
	      -A     Declares vname to be an  associative  array.   Subscripts
		     are strings rather than arithmetic expressions.
	      -a     Declares  vname to be an indexed array.  This is optional
		     unless except for compound variable assignments.
	      -E     Declares vname to be a double  precision  floating	 point
		     number.   If n is non-zero, it defines the number of sig-
		     nificant figures that  are	 used  when  expanding	vname.
		     Otherwise, ten significant figures will be used.
	      -F     Declares  vname  to  be a double precision floating point
		     number.  If n is  non-zero,  it  defines  the  number  of
		     places after the decimal point that are used when expand-
		     ing vname.	 Otherwise ten places after the decimal	 point
		     will be used.
	      -H     This  option  provides  UNIX to host-name file mapping on
		     non-UNIX machines.
	      -L     Left justify and remove leading blanks from value.	 If  n
		     is non-zero, it defines the width of the field, otherwise
		     it is determined by the  width  of	 the  value  of	 first
		     assignment.   When	 the  variable	is  assigned to, it is
		     filled on the right with blanks or truncated,  if	neces-
		     sary,  to	fit  into  the field.  The -R option is turned
		     off.
	      -R     Right justify and fill with leading blanks.  If n is non-
		     zero,  it defines the width of the field, otherwise it is
		     determined by the width of the value of first assignment.
		     The  field	 is  left filled with blanks or truncated from
		     the end if the variable is reassigned.  The -L option  is
		     turned off.
	      -Z     Right  justify  and  fill with leading zeros if the first
		     non-blank character is a digit and the -L option has  not
		     been  set.	 Remove leading zeros if the -L option is also
		     set.  If n is non-zero,  it  defines  the	width  of  the
		     field,  otherwise	it  is	determined by the width of the
		     value of first assignment.
	      -f     The names refer to function names	rather	than  variable
		     names.   No  assignments  can  be made and the only other
		     valid options are -t, -u and -x.  The -t option turns  on
		     execution	tracing	 for  this  function.	The  -u option
		     causes this function to be marked undefined.   The	 FPATH
		     variable will be searched to find the function definition
		     when the function is referenced.	If  no	options	 other
		     than  -f  is specified, then the function definition will
		     be displayed on standard output.	If  +f	is  specified,
		     then  a  line  containing the function name followed by a
		     shell comment containing the line number and path name of
		     the file where this function was defined, if any, is dis-
		     played.
	      -b     The variable can hold any number of bytes of  data.   The
		     data  can be text or binary.  The value is represented by
		     the base64 encoding of the data.  If -Z  is  also	speci-
		     fied, the size in bytes of the data in the buffer will be
		     determined by the size associated with the	 -Z.   If  the
		     base64  string  assigned results in more data, it will be
		     truncated.	 Otherwise, it will be filled with bytes whose
		     value  is zero.  The printf format %B can be used to out-
		     put the actual data in this buffer instead of the	base64
		     encoding of the data.
	      -i     Declares  vname  to be represented internally as integer.
		     The right hand side of an assignment is evaluated	as  an
		     arithmetic expression when assigning to an integer.  If n
		     is non-zero, it defines the output arithmetic base,  oth-
		     erwise the output base will be ten.
	      -l     All  upper-case  characters  are converted to lower-case.
		     The upper-case option, -u, is turned off.
	      -n     Declares vname to be a reference to  the  variable	 whose
		     name  is defined by the value of variable vname.  This is
		     usually used to reference a variable  inside  a  function
		     whose name has been passed as an argument.
	      -r     The given vnames are marked readonly and these names can-
		     not be changed by subsequent assignment.
	      -t     Tags the variables.  Tags are user definable and have  no
		     special meaning to the shell.
	      -u     All  lower-case  characters  are converted to upper-case.
		     The lower-case option, -l, is turned off.
	      -x     The given vnames are marked for automatic export  to  the
		     environment of subsequently-executed commands.  Variables
		     whose names contain a .  cannot be exported.

	      The -i attribute cannot be specified along with -R, -L,  -Z,  or
	      -f.

	      Using + rather than - causes these options to be turned off.  If
	      no vname arguments are given, a list of vnames  (and  optionally
	      the values) of the variables is printed.	(Using + rather than -
	      keeps the values from being  printed.)   The  -p	option	causes
	      typeset followed by the option letters to be printed before each
	      name rather than the names of the options.  If any option	 other
	      than  -p	is  given,  only those variables which have all of the
	      given options are printed.  Otherwise, the vnames and attributes
	      of all variables that have attributes are printed.

       ulimit [ -HSacdfmnpstv ] [ limit ]
	      Set  or display a resource limit.	 The available resource limits
	      are listed below.	 Many systems do not support one  or  more  of
	      these  limits.   The  limit for a specified resource is set when
	      limit is specified.  The value of limit can be a number  in  the
	      unit specified below with each resource, or the value unlimited.
	      The -H and -S options specify whether the hard limit or the soft
	      limit  for  the  given  resource is set.	A hard limit cannot be
	      increased once it is set.	 A soft limit can be increased	up  to
	      the  value of the hard limit.  If neither the H nor S options is
	      specified, the limit applies  to	both.	The  current  resource
	      limit  is printed when limit is omitted.	In this case, the soft
	      limit is printed unless H is  specified.	 When  more  than  one
	      resource	is  specified, then the limit name and unit is printed
	      before the value.
	      -a     Lists all of the current resource limits.
	      -c     The number of 512-byte blocks on the size of core	dumps.
	      -d     The number of K-bytes on the size of the data area.
	      -f     The  number of 512-byte blocks on files that can be writ-
		     ten by the current process or by child  processes	(files
		     of any size may be read).
	      -m     The number of K-bytes on the size of physical memory.
	      -n     The number of file descriptors plus 1.
	      -p     The number of 512-byte blocks for pipe buffering.
	      -s     The number of K-bytes on the size of the stack area.
	      -t     The number of CPU seconds to be used by each process.
	      -v     The number of K-bytes for virtual memory.

	      If no option is given, -f is assumed.

       umask [ -S ] [ mask ]
	      The user file-creation mask is set to mask (see umask(2)).  mask
	      can either be an octal number or a symbolic value	 as  described
	      in  chmod(1).  If a symbolic value is given, the new umask value
	      is the complement of the result of applying mask to the  comple-
	      ment  of the previous umask value.  If mask is omitted, the cur-
	      rent value of the mask is printed.  The  -S  option  causes  the
	      mode  to be printed as a symbolic value.	Otherwise, the mask is
	      printed in octal.

	unalias [ -a ] name ...
	      The aliases given by the list of	names  are  removed  from  the
	      alias list.  The -a option causes all the aliases to be unset.

       unset [ -fnv ] vname ...
	      The  variables given by the list of vnames are unassigned, i.e.,
	      their values and attributes are erased.  Readonly variables can-
	      not  be unset.  If the -f option is set, then the names refer to
	      function names.  If the -v option is set, then the  names	 refer
	      to  variable  names.   The -f option overrides -v.  If -n is set
	      and name is a name reference, then name  will  be	 unset	rather
	      than the variable that it references.  The default is equivalent
	      to -v.  Unsetting LINENO,	 MAILCHECK,  OPTARG,  OPTIND,  RANDOM,
	      SECONDS, TMOUT, and _ removes their special meaning even if they
	      are subsequently assigned to.

       wait [ job ... ]
	      Wait for the specified job and report  its  termination  status.
	      If  job  is not given, then all currently active child processes
	      are waited for.  The exit status from this command  is  that  of
	      the last process waited for if job is specified; otherwise it is
	      zero.  See Jobs for a description of the format of job.

       whence [ -afpv ] name ...
	      For each name, indicate how it would be interpreted if used as a
	      command name.
	      The  -v  option  produces a more verbose report.	The -f options
	      skips the search for functions.	The  -p	 option	 does  a  path
	      search  for  name	 even  if  name	 is an alias, a function, or a
	      reserved word.  The -p option turns off the -v option.   The  -a
	      option  is  similar  to the -v option but causes all interpreta-
	      tions of the given name to be reported.

   Invocation.
       If the shell is invoked by exec(2), and the first character of argument
       zero  ($0) is -, then the shell is assumed to be a login shell and com-
       mands are read from /etc/profile and then from either .profile  in  the
       current	directory or $HOME/.profile, if either file exists.  Next, for
       interactive shells, commands are read from the file named by performing
       parameter  expansion, command substitution, and arithmetic substitution
       on the value of the environment variable ENV if the  file  exists.   If
       the  -s	option	is  not	 present and arg and a file by the name of arg
       exits, then it reads and executes this script.  Otherwise, if the first
       arg  does  not contain a /, a path search is performed on the first arg
       to determine the name of the script to execute.	The  script  arg  must
       have  execute  permission  and  any  setuid and setgid settings will be
       ignored.	 If the script is not found on the path, arg is	 processed  as
       if  it named a built-in command or function.  Commands are then read as
       described below; the following options are  interpreted	by  the	 shell
       when it is invoked:

       -c	 If  the -c option is present, then commands are read from the
		 first arg.  Any remaining arguments become positional parame-
		 ters starting at 0.
       -s	 If  the  -s option is present or if no arguments remain, then
		 commands are read from the  standard  input.	Shell  output,
		 except	 for  the output of the Special Commands listed above,
		 is written to file descriptor 2.
       -i	 If the -i option is present or if the shell input and	output
		 are  attached	to  a terminal (as told by tcgetattr(2)), then
		 this shell is interactive.  In this case TERM is ignored  (so
		 that  kill  0 does not kill an interactive shell) and INTR is
		 caught and ignored (so that wait is interruptible).   In  all
		 cases, QUIT is ignored by the shell.
       -r	 If the -r option is present, the shell is a restricted shell.
       -D	 A list of all double quoted strings that are preceded by a  $
		 will  be  printed on standard output and the shell will exit.
		 This set of strings will be subject to	 language  translation
		 when  the locale is not C or POSIX.  No commands will be exe-
		 cuted.

       -P	 If -P or -o profile is present, the shell is a profile	 shell
		 (see pfexec(1)).

       -R filename
		 The  -R filename option is used to generate a cross reference
		 database that can be used by a separate utility to find defi-
		 nitions and references for variables and commands.

       The remaining options and arguments are described under the set command
       above.  An optional - as the first argument is ignored.

   Rksh Only.
       Rksh is used to set up login names  and	execution  environments	 whose
       capabilities are more controlled than those of the standard shell.  The
       actions of rksh are identical to those of ksh, except that the  follow-
       ing are disallowed:
	      Unsetting the restricted option.
	      changing directory (see cd(1)),
	      setting  or  unsetting  the  value  or attributes of SHELL, ENV,
	      FPATH, or PATH,
	      specifying path or command names containing /,
	      redirecting output (>, >|, <>, and >>).
	      adding or deleting built-in commands.
	      using command -p to invoke a command.

       The restrictions above are enforced after .profile and  the  ENV	 files
       are interpreted.

       When  a	command	 to be executed is found to be a shell procedure, rksh
       invokes ksh to execute it.  Thus, it is possible to provide to the end-
       user  shell  procedures that have access to the full power of the stan-
       dard shell, while imposing a limited  menu  of  commands;  this	scheme
       assumes	that  the end-user does not have write and execute permissions
       in the same directory.

       The net effect of these rules is that the writer of  the	 .profile  has
       complete	 control  over	user  actions,	by performing guaranteed setup
       actions and leaving the user in an appropriate directory (probably  not
       the login directory).

       The  system  administrator often sets up a directory of commands (e.g.,
       /usr/rbin) that can be safely invoked by rksh.

EXIT STATUS
       Errors detected by the shell, such as syntax errors, cause the shell to
       return a non-zero exit status.  If the shell is being used non-interac-
       tively, then execution of the shell file is abandoned unless the	 error
       occurs inside a subshell in which case the subshell is abandoned.  Oth-
       erwise, the shell returns the exit status of the last command  executed
       (see  also  the	exit  command above).  Run time errors detected by the
       shell are reported by printing the command or  function	name  and  the
       error  condition.   If  the  line  number that the error occurred on is
       greater than one, then the line number is also printed in square brack-
       ets ([]) after the command or function name.

FILES
       /etc/profile  The  system  wide initialization file, executed for login
       shells.
       $HOME/.profile
	      The personal initialization  file,  executed  for	 login	shells
	      after /etc/profile.
       $HOME/..kshrc
	      Default  personal	 initialization file, executed for interactive
	      shells when ENV is not set.
       /etc/suid_profile
	      Alternative initialization file, executed when instead  of  per-
	      sonal  initialization  file  when the real and effective user or
	      group id do not match.
       /dev/null
	      NULL device

SEE ALSO
       cat(1), cd(1), chmod(1), cut(1), egrep(1), echo(1),  emacs(1),  env(1),
       fgrep(1),  gmacs(1),  grep(1),  newgrp(1), pfexec(1), stty(1), test(1),
       umask(1),  vi(1),  dup(2),  exec(2),  fork(2),  getpwnam(3),  ioctl(2),
       lseek(2),   paste(1),   pathconf(2),   pipe(2),	sysconf(2),  umask(2),
       ulimit(2), wait(2), rand(3), a.out(5), profile(5), environ(7).

       Morris I. Bolsky and David G. Korn, The New KornShell Command and  Pro-
       gramming Language, Prentice Hall, 1995.

       POSIX  -	 Part  2:  Shell  and Utilities, IEEE Std 1003.2-1992, ISO/IEC
       9945-2, IEEE, 1993.

CAVEATS
       If a command is executed, and then a command  with  the	same  name  is
       installed  in a directory in the search path before the directory where
       the original command was found, the shell will  continue	 to  exec  the
       original	 command.   Use	 the -t option of the alias command to correct
       this situation.

       Some very old shell scripts contain a ^ as a synonym for the pipe char-
       acter |.

       Using  the  hist	 built-in command within a compound command will cause
       the whole command to disappear from the history file.

       The built-in command . file reads the whole file	 before	 any  commands
       are  executed.	Therefore, alias and unalias commands in the file will
       not apply to any commands defined in the file.

       Traps are not processed	while  a  job  is  waiting  for	 a  foreground
       process.	  Thus,	 a trap on CHLD won't be executed until the foreground
       job terminates.

       It is a good idea to leave a space after the comma operator  in	arith-
       metic  expressions  to  prevent the comma from being interpreted as the
       decimal point character in certain locales.

RDS Standard		  User Environment Utilities			KSH(1)
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