set tabs on a terminal
tabs [ tabspec ] [ -T type ]
[ +mn ]
tabs [ -T type ]
[ +m [ n ] ] n1
[, n2 ... ]
The tabs command sets the tab stops on the user's terminal
according to the tab specification tabspec, after clearing
any previous settings.
It also optionally adjusts the margin.
The user's terminal must have remotely-settable hardware tabs.
Any of the following also may be used; if a given flag occurs more
than once, the last value given takes effect:
The four types of acceptable tab specification for tabspec
are canned (-code), repetitive
(-n), arbitrary (n1,n2, ...),
and file (--file). These are
described below. If no tabspec is given, the default
value is ``-8'', that is, ``standard'' UNIX tabs. The lowest
column number is 1. Note that for tabs, column 1 always
refers to the leftmost column on a terminal, even one whose column
markers begin at 0, for example, the DASI 300,
DASI 300s, and DASI 450.
Select a canned set of tabs with -code set to:
Assembler, IBM S/370, first format
Assembler, IBM S/370, second format
COBOL, normal format
COBOL compact format (columns 1-6 omitted). Using this
code, the first typed character corresponds to card column 7, one
space gets you to column 8, and a tab reaches column 12. Files
using this tab setup should include a format specification as
<:t-c2 m6 s66 d:>
COBOL compact format (columns 1-6 omitted), with more tabs
than -c2. This is the recommended format for
COBOL. The appropriate format specification is (see
<:t-c3 m6 s66 d:>
UNIVAC 1100 Assembler
A repetitive specification requests tabs at columns
1+n, 1+2n, etc. Of particular importance is
the value 8: this represents the ``standard'' UNIX tab
setting, and is the most likely tab setting to be found at a
terminal. Another special case is the value 0, implying no
tabs at all.
The arbitrary format permits the user to type any chosen
set of numbers, separated by commas, in ascending order. Up to 40
numbers are allowed. If any number (except the first one) is
preceded by a plus sign, it is taken as an increment to be added to
the previous value. Thus, the formats
1,10,+10,+10 are considered
If the name of a file is given, tabs reads the
first line of the file, searching for a format specification (see
If it finds one there, it sets the tab stops according to it:
otherwise it sets them as -8. This type of specification
may be used to make sure that a tabbed file is printed with correct
tab settings, and would be used with the
tabs -- file; pr file
Tab and margin setting is performed via the standard output.
tabs usually needs to know the type of terminal in order
to set tabs and always needs to know the type to set
margins. type is a name listed in
If no -T flag is supplied, tabs uses the value
of the environment variable TERM. If TERM is not
defined in the environment (see
tabs tries a sequence that will work for many terminals.
The margin argument may be used for some terminals. It causes all
tabs to be moved over n columns by making column
n+1 the left margin. If +m is given
without a value of n, the value assumed is
10. For a TermiNet, the first value in the tab list should
be 1, or the margin will move even further to the
right. The normal (leftmost) margin on most terminals is obtained by
+m0. The margin for most terminals is reset only when the
+m flag is given explicitly.
tabs returns 0 if no error occurred, or 1 if an error
When arbitrary tabs are ordered incorrectly.
When a zero or missing increment is found in an arbitrary
unknown tab code
When a canned code cannot be found.
If --file option used and file can't
If --file option used and the specification in
that file points to yet another file. Indirection of this
form is not permitted.
Example using -code (canned specification) to
set tabs to the settings required by the IBM assembler:
columns 1, 10, 16, 36, 72.
Example of using -n (repetitive specification),
where n is 8, causes tabs to be set every eighth
1+(18), 1+(28), ... which evaluate to columns 9,
Example of using n1,n2, ...
(arbitrary specification) to set tabs at columns 1, 8, and
Example of using --file (file specification)
to indicate that tabs should be set according to the first line of
There is no consistency among different terminals regarding ways of
clearing tabs and setting the left margin.
The tabs command clears only 20 tabs (on terminals
requiring a long sequence), but is willing to set 64.
The tabspec used with the tabs command is
different from the one used with the
command. For example, tabs -8 sets every eighth position;
whereas newform -i-8 indicates that tabs are set every
tabs is conformant with:
ISO/IEC DIS 99452:1992, Information technology Portable Operating System Interface (POSIX) Part 2: Shell and Utilities (IEEE Std 1003.21992);
AT&T SVID Issue 2;
X/Open CAE Specification, Commands and Utilities, Issue 4, 1992.
© 2003 Caldera International, Inc. All rights reserved.
SCO OpenServer Release 5.0.7 -- 11 February 2003