tabs(1)tabs(1)NAMEtabs - Sets tab stops on terminals
SYNOPSIStabs [-n] [-T terminal] [+m [margin]]
tabs [predefined_tab_flag] [-T terminal] [+m [margin]]
tabs [-T terminal] [+m [margin]] number [,number]...
tabs [--tab_format_file]
The tabs command clears up to 20 previous tabs and sets up to 40 tabs
on the terminal according to the supplied tab specifications.
STANDARDS
Interfaces documented on this reference page conform to industry stan‐
dards as follows:
tabs: XCU5.0
Refer to the standards(5) reference page for more information about
industry standards and associated tags.
OPTIONS
Specifies repetitive tab stops separated by a uniform number of column
positions, n, where n is a single-digit number. The default usage of
tabs with no arguments is equivalent to tabs-8. If you use -0, the tab
stops are cleared and no new ones are set. Identifies the terminal so
that tabs can set tabs and margins correctly. The terminal argument is
one of the conventional terminal names supported by your system.
[Tru64 UNIX] If the terminal you specify is not known to the
system, tabs tries a general value that works for most termi‐
nals.
If you do not provide a -T option, tabs uses the TERM shell
variable. Moves all tabs to the right number columns, and makes
column number+1 the left margin.
If m is given without a value, 10 is assumed. The leftmost mar‐
gin on most terminals is defined by m0. Specifies that tabs
should be set to a structured language format that is known to
the system. See the section Predefined Tab Flags for a descrip‐
tion of these flags. [Tru64 UNIX] Causes tabs to read a file
named tab_format_file for format information. The first line of
the file must be in the format shown in the section Format Spec‐
ifications to use this method. The file may contain other lines
which are ignored by tabs.
Note
[Tru64 UNIX] The double dash (--) format is mandatory with this
option.
OPERANDS
Sets tabs at the named column numbers (a list in ascending order, sepa‐
rated by commas). You can specify up to 40 numbers. If any number
except the first has a plus sign prefix, the prefixed number is added
to the previous number for the next setting. Thus, the tab lists
1,10,20,30 and 1,10,+10,+10 provide the same tab settings.
DESCRIPTION
If you use the tabs command with no options or operands, the terminal
tabs are reset to the system defaults for your terminal type. If only
the -T option is used, tabs are reset to the defaults for that terminal
type.
[Tru64 UNIX] When you use the tabs command, always consider the left‐
most column number to be 1, even if your terminal refers to it as 0
(zero). Tab-stop position n means that tabbing to position n causes
the next character output to be in the n+1th column position on that
line.
Predefined Tab Flags
[Tru64 UNIX] The flags described in the following list provide formats
required by most structured programming languages. Some of these flags
require that a particular format line be present in the file being
manipulated. This is indicated in the list. Sets the tabs to 1, 10,
16, 36, and 72. Sets the tabs to 1, 10, 16, 40, and 72. Sets the tabs
to 1, 8, 12, 16, 20, and 55 (COBOL normal format) Sets the tabs to 1,
6, 10, 14, and 49 (COBOL compact format, columns 1 to 6 omitted). With
this code, the first column position corresponds to card column 7. One
space gets you to column 8, and a tab reaches column 12. Files using
this code must include the following format specification:
<:t-c2 m6 s66 d:>
[Tru64 UNIX] See Format Specifications later in this reference
page. Sets the tabs to 1, 6, 10, 14, 18, 22, 26, 30, 34, 38,
42, 46, 50, 54, 58, 62, and 67 (COBOL compact format with more
tabs than -c2). This is the recommended format for COBOL.
Files using this code must include the following format specifi‐
cation:
<:t-c3 m6 s66 d:> Sets the tabs to 1, 7, 11, 15, 19, and 23
(FORTRAN). Sets the tabs to 1, 5, 9, 13, 17, 21, 25, 29, 33,
37, 41, 45, 49, 53, 57, and 61 (PL/I). Sets the tabs to 1, 10,
and 55 (SNOBOL). Sets the tabs to 1, 12, 20, and 44.
Format Specifications
[Tru64 UNIX] A format specification consists of a sequence of argu‐
ments separated by blanks and enclosed in brackets and colons: <: :>.
Each argument consists of a keyletter and an optional value which imme‐
diately follows it. The following arguments can be used: [Tru64
UNIX] Specifies tab settings. The value for tabs can be: [Tru64
UNIX] A list of column numbers separated by commas, indicating tab
stops at the specified columns. [Tru64 UNIX] A - (dash) followed by a
number n, specifying tabs stops every n columns. [Tru64 UNIX] A pre‐
set tab specification, for example -a2. [Tru64 UNIX] Specifies a max‐
imum line size, or length. The size specification must be an integer.
(The value of size is checked after tabs have been expanded but before
the margin is prepended.) [Tru64 UNIX] Specifies a number of spaces
to be inserted at the beginning of each line. The margin specification
must be an integer. [Tru64 UNIX] Indicates that the line containing
the format specification is to be deleted from the converted file.
[Tru64 UNIX] If a format specification can be disguised as a
comment, for example * <:t5,10,15 s75 m5:> *, you do not need to
include the d keyletter. [Tru64 UNIX] Indicates that the cur‐
rent format should prevail only until another format specifica‐
tion is encountered in the file.
[Tru64 UNIX] Default values of t-8 and m0 are assumed if t and m argu‐
ments are not included in the specification; if s is not included, line
size is not checked. If the first line of a file does not contain a
format specification, these defaults are assumed for the entire file.
NOTES
The tabs command assumes that standard output is the terminal. If
standard output is redirected, the results are unpredicable. Full
operation of all capabilities may be restricted by the hardware.
EXIT STATUS
The following exit values are returned: Successful completion. An
error occurred.
EXAMPLES
To set tabs every four spaces, enter: tabs-4 To clear all tabs, enter:
tabsENVIRONMENT VARIABLES
The following environment variables affect the execution of tabs: Pro‐
vides a default value for the internationalization variables that are
unset or null. If LANG is unset or null, the corresponding value from
the default locale is used. If any of the internationalization vari‐
ables contain an invalid setting, the utility behaves as if none of the
variables had been defined. If set to a non-empty string value, over‐
rides the values of all the other internationalization variables.
Determines the locale for the interpretation of sequences of bytes of
text data as characters (for example, single-byte as opposed to multi-
byte characters in arguments). Determines the locale for the format
and contents of diagnostic messages written to standard error. Deter‐
mines the location of message catalogues for the processing of LC_MES‐
SAGES. Determines the terminal type if the -T option is not used.
SEE ALSO
Commands: expand(1), nroff(1), stty(1), tset(1)
Standards: standards(5)tabs(1)
