limits.h man page on OpenIndiana

Man page or keyword search:  
man Server   20441 pages
apropos Keyword Search (all sections)
Output format
OpenIndiana logo
[printable version]

limits.h(3HEAD)			    Headers		       limits.h(3HEAD)

NAME
       limits.h, limits - implementation-defined constants

SYNOPSIS
       #include <limits.h>

DESCRIPTION
       The  <limits.h>	header defines various symbolic names. Different cate‐
       gories of names are described below.

       The names represent various limits on resources that the implementation
       imposes	on applications. Symbolic constant names beginning with _POSIX
       can be found in unistd.h(3HEAD).

       Applications should not assume any particular value  for	 a  limit.  An
       application  wishing  to	 avail itself of the full amount of a resource
       available on an implementation can make use of the value given in  lim‐
       its.h  on  that	particular  implementation by using the symbolic names
       listed below. Many of the listed limits are not invariant, and at  run‐
       time,  the  value  of  the  limit might differ from those given in this
       header, for the following reasons:

	   o	  The limit is pathname-dependent.

	   o	  The limit differs between the compile and runtime machines.

       For these reasons, an  application  can	use  the  fpathconf(2),	 path‐
       conf(2),	 and  sysconf(3C) functions to determine the actual value of a
       limit at runtime.

   Runtime Invariant Values (Possibly Indeterminate)
       AIO_LISTIO_MAX

	   Maximum number of I/O operations in a single	 list  I/O  call  sup‐
	   ported by the implementation.

       AIO_MAX

	   Maximum number of outstanding asynchronous I/O operations supported
	   by the implementation.

       AIO_PRIO_DELTA_MAX

	   The maximum amount by which a process can decrease its asynchronous
	   I/O priority level from its own scheduling priority.

       ARG_MAX

	   Maximum length of argument to the exec(2) functions including envi‐
	   ronment data.

       ATEXIT_MAX

	   Maximum number of functions that can be registered with atexit(3C).

       CHILD_MAX

	   Maximum number of simultaneous processes per real user ID.

       CLK_TCK

	   Number of clock ticks per second returned by the times(2) function.

       DELAYTIMER_MAX

	   Maximum number of timer expiration overruns.

       HOST_NAME_MAX

	   Maximum length of a host name (not including the terminating	 null)
	   as returned from the gethostname(3C) function.

       IOV_MAX

	   Maximum  number  of iovec structures that one process has available
	   for use with read(2) or write(2).

       LOGIN_NAME_MAX

	   Maximum length of a login name.

       MQ_OPEN_MAX

	   The maximum number of open message queue descriptors a  process  is
	   allowed to hold.

       LOGIN_NAME_MAX

	   Maximum length of a login name.

       MQ_OPEN_MAX

	   The	maximum	 number of open message queue descriptors a process is
	   allowed to hold.

       MQ_PRIO_MAX

	   The maximum number of message priorities supported by the implemen‐
	   tation.

       OPEN_MAX

	   Maximum  number  of files that one process can have open at any one
	   time.

       PAGESIZE

	   Size in bytes of a page.

       PAGE_SIZE

	   Equivalent to PAGESIZE. If either PAGESIZE or PAGE_SIZE is defined,
	   the other is defined with the same value.

       PASS_MAX

	   The	maximum number of significant bytes in a password, not includ‐
	   ing the terminating null.

       PTHREAD_DESTRUCTOR_ITERATIONS

	   Maximum number of attempts made to destroy a	 thread's  thread-spe‐
	   cific data values on thread exit.

       PTHREAD_KEYS_MAX

	   Maximum number of data keys that can be created by a process.

       PTHREAD_STACK_MIN

	   Minimum size in bytes of thread stack storage.

       PTHREAD_THREADS_MAX

	   Maximum number of threads that can be created per process.

       RE_DUP_MAX

	   The	number	of  repeated  occurrences  of  a  BRE permitted by the
	   regexec(3C) and regcomp(3C) functions when using the interval nota‐
	   tion {\(m,n\}.

       RTSIG_MAX

	   Maximum  number of realtime signals reserved for application use in
	   this implementation.

       SEM_NSEMS_MAX

	   Maximum number of semaphores that a process can have.

       SEM_VALUE_MAX

	   The maximum value a semaphore can have.

       SIGQUEUE_MAX

	   Maximum number of queued signals that a process can send  and  have
	   pending at the receiver(s) at any time.

       SS_REPL_MAX

	   The maximum number of replenishment operations that may be simulta‐
	   neously pending for a particular sporadic server scheduler.

       STREAM_MAX

	   The number of streams that one process can have open at  one	 time.
	   If defined, it has the same value as FOPEN_MAX.

       SYMLOOP_MAX

	   Maximum  number of symbolic links that can be reliably traversed in
	   the resolution of a pathname in the absence of a loop.

       TIMER_MAX

	   Maximum number of timers per process supported by  the  implementa‐
	   tion.

       TRACE_EVENT_NAME_MAX

	   Maximum length of the trace event name.

       TRACE_NAME_MAX

	   Maximum  length  of	the  trace generation version string or of the
	   trace stream name.

       TRACE_SYS_MAX

	   Maximum number of trace streams that may  simultaneously  exist  in
	   the system.

       TRACE_USER_EVENT_MAX

	   Maximum number of user trace event type identifiers that may simul‐
	   taneously exist in a traced process, including the predefined  user
	   trace event POSIX_TRACE_UNNAMED_USER_EVENT.

       TTY_NAME_MAX

	   Maximum length of terminal device name.

       TZNAME_MAX

	   Maximum  number  of bytes supported for the name of a timezone (not
	   of the TZ variable).

   Pathname Variable Values
       The values in the following list can be constants within an implementa‐
       tion  or	 can vary from one pathname to another. For example, file sys‐
       tems or directories can have different characteristics. The value  sup‐
       ported for a specific pathname is provided by the pathconf(2) function.

       FILESIZEBITS		   Minimum number of bits needed to represent,
				   as a signed integer value, the maximum size
				   of  a regular file allowed in the specified
				   directory.

       LINK_MAX			   Maximum number of links to a single file.

       MAX_CANON		   Maximum  number  of	bytes  in  a  terminal
				   canonical input line.

       MAX_INPUT		   Minimum  number of bytes for which space is
				   available in a terminal input queue; there‐
				   fore,  the  maximum	number of bytes a con‐
				   forming application may require to be typed
				   as input before reading them.

       NAME_MAX			   Maximum  number of bytes in a filename (not
				   including terminating null).

       PATH_MAX			   Maximum number  of  bytes  in  a  pathname,
				   including the terminating null character.

       PIPE_BUF			   Maximum  number of bytes that is guaranteed
				   to be atomic when writing to a pipe.

       POSIX_ALLOC_SIZE_MIN	   Minimum number of bytes of storage actually
				   allocated for any portion of a file.

       POSIX_REC_INCR_XFER_SIZE	   Recommended	increment  for	file  transfer
				   sizes between  the  POSIX_REC_MIN_XFER_SIZE
				   and POSIX_REC_MAX_XFER_SIZE values.

       POSIX_REC_MAX_XFER_SIZE	   Maximum recommended file transfer size.

       POSIX_REC_MIN_XFER_SIZE	   Minimum recommended file transfer size.

       POSIX_REC_XFER_ALIGN	   Recommended file transfer buffer alignment.

       SYMLINK_MAX		   Maximum number of bytes in a symbolic link.

   Runtime Increasable Values
       The  magnitude  limitations in the following list are fixed by specific
       implementations. An application should assume that the  value  supplied
       by <limits.h> in a specific implementation is the minimum that pertains
       whenever the application is run under that implementation.  A  specific
       instance	 of  a specific implementation can increase the value relative
       to that supplied by <limits.h>  for  that  implementation.  The	actual
       value  supported	 by a specific instance is provided by the sysconf(3C)
       function.

       BC_BASE_MAX	     Maximum obase values allowed by the  bc(1)	 util‐
			     ity.

       BC_DIM_MAX	     Maximum  number of elements permitted in an array
			     by the bc utility.

       BC_SCALE_MAX	     Maximum scale value allowed by the bc utility.

       BC_STRING_MAX	     Maximum length of a string constant  accepted  by
			     the bc utility.

       CHARCLASS_NAME_MAX    Maximum  number  of  bytes	 in  a character class
			     name.

       COLL_WEIGHTS_MAX	     Maximum number of weights that can be assigned to
			     an	 entry	of the LC_COLLATE order keyword in the
			     locale definition file.

       EXPR_NEST_MAX	     Maximum number of expressions that can be	nested
			     within parentheses by the expr(1) utility.

       EXPR_NEST_MAX	     Maximum  number of expressions that can be nested
			     within parentheses by the expr utility.

       LINE_MAX		     Unless otherwise noted, the  maximum  length,  in
			     bytes, of a utility's input line (either standard
			     input or  another	file),	when  the  utility  is
			     described	as  processing	text files. The length
			     includes room for the trailing <newline>.

       NGROUPS_MAX	     Maximum  number  of  simultaneous	 supplementary
			     group IDs per process.

       RE_DUP_MAX	     Maximum number of repeated occurrences of a regu‐
			     lar expression permitted when using the  interval
			     notation \{m,n\}.

   Maximum Values
       The symbolic constants in the following list are symbolic names for the
       most restrictive value for certain features on an  implementation  sup‐
       porting the POSIX Timers option.

       _POSIX_CLOCKRES_MIN    The  resolution  of the CLOCK_REALTIME clock, in
			      nanoseconds.

   Minimum Values
       The symbolic constants in the following list are symbolic names for the
       most  restrictive  value for certain features on an implementation con‐
       forming to various POSIX and Single  Unix  Specification	 requirements.
       See standards(5).

       _POSIX_AIO_LISTIO_MAX

	   The	number	of  I/O operations that can be specified in a list I/O
	   call.

       _POSIX_AIO_MAX

	   The number of outstanding asynchronous I/O operations.

       _POSIX_ARG_MAX

	   Maximum length of argument to the exec(2) functions including envi‐
	   ronment data.

       _POSIX_CHILD_MAX

	   Maximum number of simultaneous processes per real user ID.

       _POSIX_DELAYTIMER_MAX

	   The number of timer expiration overruns.

       _POSIX_HOST_NAME_MAX

	   Maximum  length of a host name (not including the terminating null)
	   as returned from the gethostname(3C) function.

       _POSIX_LINK_MAX

	   Maximum number of links to a single file.

       _POSIX_LOGIN_NAME_MAX

	   The size of the storage  required  for  a  login  name,  in	bytes,
	   including the terminating null.

       _POSIX_MAX_CANON

	   Maximum number of bytes in a terminal canonical input queue.

       _POSIX_MAX_INPUT

	   Maximum number of bytes allowed in a terminal input queue.

       _POSIX_MQ_OPEN_MAX

	   The number of message queues that can be open for a single process.

       _POSIX_MQ_PRIO_MAX

	   The maximum number of message priorities supported by the implemen‐
	   tation.

       _POSIX_NAME_MAX

	   Maximum number of bytes in a filename  (not	including  terminating
	   null).

       _POSIX_NGROUPS_MAX

	   Maximum number of simultaneous supplementary group IDs per process.

       _POSIX_OPEN_MAX

	   Maximum  number  of files that one process can have open at any one
	   time.

       _POSIX_PATH_MAX

	   Maximum number of bytes in a pathname.

       _POSIX_PIPE_BUF

	   Maximum number of bytes that is guaranteed to be atomic when	 writ‐
	   ing to a pipe.

       _POSIX_RE_DUP_MAX

	   The	number	of  repeated  occurrences  of  a  BRE permitted by the
	   regexec() and regcomp() functions when using the interval  notation
	   {\(m,n\}

       _POSIX_RTSIG_MAX

	   The number of realtime signal numbers reserved for application use.

       _POSIX_SEM_NSEMS_MAX

	   The number of semaphores that a process can have.

       _POSIX_SEM_VALUE_MAX

	   The maximum value a semaphore can have.

       _POSIX_SIGQUEUE_MAX

	   The number of queued signals that a process can send and have pend‐
	   ing at the receiver(s) at any time.

       _POSIX_SSIZE_MAX

	   The value that can be stored in an object of type ssize_t.

       _POSIX_STREAM_MAX

	   The number of streams that one process can have open at one time.

       _POSIX_SS_REPL_MAX

	   The number of replenishment operations that can  be	simultaneously
	   pending for a particular sporadic server scheduler.

       _POSIX_SYMLINK_MAX

	   The number of bytes in a symbolic link.

       _POSIX_SYMLOOP_MAX

	   The	number	of symbolic links that can be traversed in the resolu‐
	   tion of a pathname in the absence of a loop.

       _POSIX_THREAD_DESTRUCTOR_ITERATIONS

	   The number of attempts made to destroy a  thread's  thread-specific
	   data values on thread exit.

       _POSIX_THREAD_KEYS_MAX

	   The number of data keys per process.

       _POSIX_THREAD_THREADS_MAX

	   The number of threads per process.

       _POSIX_TIMER_MAX

	   The per-process number of timers.

       _POSIX_TRACE_EVENT_NAME_MAX

	   The length in bytes of a trace event name.

       _POSIX_TRACE_NAME_MAX

	   The length in bytes of a trace generation version string or a trace
	   stream name.

       _POSIX_TRACE_SYS_MAX

	   The number of trace streams that can simultaneously	exist  in  the
	   system.

       _POSIX_TRACE_USER_EVENT_MAX

	   The number of user trace event type identifiers that may simultane‐
	   ously exist in a traced  process,  including	 the  predefined  user
	   trace event POSIX_TRACE_UNNAMED_USER_EVENT.

       _POSIX_TTY_NAME_MAX

	   The	size  of  the  storage required for a terminal device name, in
	   bytes, including the terminating null.

       _POSIX_TZNAME_MAX

	   Maximum number of bytes supported for the name of a	timezone  (not
	   of the TZ variable).

       _POSIX2_BC_BASE_MAX

	   Maximum obase values allowed by the bc utility.

       _POSIX2_BC_DIM_MAX

	   Maximum number of elements permitted in an array by the bc utility.

       _POSIX2_BC_SCALE_MAX

	   Maximum scale value allowed by the bc utility.

       _POSIX2_BC_STRING_MAX

	   Maximum length of a string constant accepted by the bc utility.

       _POSIX2_CHARCLASS_NAME_MAX

	   Maximum number of bytes in a character class name.

       _POSIX2_COLL_WEIGHTS_MAX

	   Maximum  number  of weights that can be assigned to an entry of the
	   LC_COLLATE order keyword in the locale definition file.

       _POSIX2_EXPR_NEST_MAX

	   Maximum number of expressions that can be nested within parentheses
	   by the expr utility.

       _POSIX2_LINE_MAX

	   Unless  otherwise  noted,  the maximum length, in bytes, of a util‐
	   ity's input line (either standard input or another file), when  the
	   utility  is described as processing text files. The length includes
	   room for the trailing <newline>.

       _POSIX2_RE_DUP_MAX

	   Maximum number of repeated occurrences of a regular expression per‐
	   mitted when using the interval notation \{m,n\}.

       _XOPEN_IOV_MAX

	   Maximum  number  of iovec structures that one process has available
	   for use with read(2) or write(2).

       _XOPEN_NAME_MAX

	   Maximum number of bytes in a filename (not including the  terminat‐
	   ing null).

       _XOPEN_PATH_MAX

	   Maximum number of bytes in a pathname.

   Numerical Limits
       The  values  in	the following lists shall be defined in <limits.h> and
       are constant expressions suitable for use in #if	 preprocessing	direc‐
       tives.  Moreover,  except  for  CHAR_BIT,  DBL_DIG,  DBL_MAX,  FLT_DIG,
       FLT_MAX, LONG_BIT, WORD_BIT, and MB_LEN_MAX,  the  symbolic  names  are
       defined as expressions of the correct type.

       If  the	value of an object of type char is treated as a signed integer
       when used in an expression, the value of CHAR_MIN is the same  as  that
       of  SCHAR_MIN  and  the	value  of  CHAR_MAX  is	 the  same  as that of
       SCHAR_MAX. Otherwise, the value of CHAR_MIN  is	0  and	the  value  of
       CHAR_MAX is the same as that of UCHAR_MAX.

       CHAR_BIT	     Number of bits in a type char.

       CHAR_MAX	     Maximum value of type char.

       CHAR_MIN	     Minimum value of type char.

       DBL_DIG	     Digits of precision of type double.

       DBL_MAX	     Maximum decimal value of a double.

       DBL_MIN	     Minimum decimal value of a double.

       FLT_DIG	     Digits of precision of type float.

       FLT_MAX	     Maximum decimal value of a float.

       FLT_MIN	     Minimum decimal value of a float.

       INT_MIN	     Minimum value of type int.

       INT_MAX	     Maximum value of an int.

       LLONG_MIN     Minimum value of type long long.

       LLONG_MAX     Maximum value of type long long.

       LONG_BIT	     Number of bits in a long.

       LONG_MIN	     Minimum value of type long.

       LONG_MAX	     Maximum value of a long.

       MB_LEN_MAX    Maximum number of bytes in a character, for any supported
		     locale.

       SCHAR_MIN     Minimum value of type signed char.

       SCHAR_MAX     Maximum value of type signed char.

       SHRT_MIN	     Minimum value of type short.

       SHRT_MAX	     Maximum value of type short.

       SSIZE_MAX     Maximum value of an object of type ssize_t.

       TMP_MAX	     Minimum number  of	 unique	 filename  generated  by  tmp‐
		     nam(3C).  Maximum number of times an application can call
		     tmpnam() reliably.

       UCHAR_MAX     Maximum value of type unsigned char.

       UINT_MAX	     Maximum value of type unsigned.

       ULLONG_MAX    Maximum value of type unsigned long long.

       ULONG_MAX     Maximum value of type unsigned long.

       USHRT_MAX     Maximum value for a type unsigned short.

       WORD_BIT	     Number of bits in a word or type int.

   Other Invariant Values
       The following constants are defined in <limits.h>.

       CHARCLASS_NAME_MAX    Maximum number of	bytes  in  a  character	 class
			     name.

       LOGNAME_MAX	     The maximum number of bytes supported in a user's
			     login name.

       NL_ARGMAX	     Maximum value of digit in calls to the printf(3C)
			     and scanf(3C) functions.

       NL_LANGMAX	     Maximum number of bytes in a LANG name.

       NL_MSGMAX	     Maximum message number.

       NL_NMAX		     Maximum  number  of  bytes in an N-to-1 collation
			     mapping.

       NL_SETMAX	     Maximum set number.

       NL_TEXTMAX	     Maximum number of bytes in a message string.

       NZERO		     Default process priority.

SEE ALSO
       fpathconf(2), pathconf(2), sysconf(3C), standards(5)

SunOS 5.11			 8 April 2004		       limits.h(3HEAD)
[top]

List of man pages available for OpenIndiana

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net