tabs(1)
tabs --
set tabs on a terminal
Synopsis
tabs [tabspec] [-Ttype] [+mn]
Description
tabs
sets the tab stops on the user's terminal according to the tab specification
tabspec,
after clearing any previous settings.
The user's terminal must have remotely settable hardware tabs.
Options
The tabspec argument can be any one of:
canned (-code), repetitive (-n),
arbitrary (n1, n2, . . . ),
or file (--file).
If no
tabspec
is given, the default value is
-8,
that is,
UNIX system ``standard'' 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.
-code-
Use one of the codes listed below to select a
``canned'' set of tabs.
The valid codes and their meanings are as follows:
-a-
1,10,16,36,72
Assembler, IBM S/370, first format
-a2-
1,10,16,40,72
Assembler, IBM S/370, second format
-c-
1,8,12,16,20,55
COBOL, normal format
-c2-
1,6,10,14,49
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 follows (see
fspec(4)):
<:t-c2 m6 s66 d:>
-c3-
1,6,10,14,18,22,26,30,34,38,42,46,50,54,58,62,67
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
fspec(4)]:
<:t-c3 m6 s66 d:>
-f-
1,7,11,15,19,23
FORTRAN
-p-
1,5,9,13,17,21,25,29,33,37,41,45,49,53,57,61
PL/I
-s-
1,10,55
SNOBOL
-u-
1,12,20,44
UNIVAC 1100 Assembler
-n-
A ``repetitive'' specification requests tabs at columns
1+n,
1+2n,
etc.
Of particular importance is the value
8:
this represents the
UNIX system ``standard'' 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.
n1,n2,...-
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
1,10,20,30,
and
1,10,+10,+10
are considered identical.
--file-
If the name of a file is given,
tabs
reads the first line of the file, searching for a format specification [see
fspec(4)].
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
pr
command:
tabs -- file; pr file
Any of the following also may be used;
if a given flag occurs more than once,
the last value given takes effect:
-Ttype-
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
term(5).
If no
-T
flag is supplied,
tabs
uses the value of the environment variable
TERM.
If
TERM
is not defined
in the
environment
[see
environ(5)],
tabs
tries a sequence that will work for many terminals.
If the environment variable POSIX2 is set to any value and
exported, then tabs displays a warning message when the
terminal type does not support tab settings.
+mn-
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.
Tab and margin setting is performed via the standard output.
Usage
tabs -a-
example using
-code
(``canned'' specification) to set
tabs to the settings required by the IBM
assembler: columns 1, 10, 16, 36, 72.
tabs -8-
example of using
-n
(``repetitive'' specification), where
n
is
8,
causes tabs to be set every eighth position:
1+(1*8), 1+(2*8), . . . , which evaluate to columns
9, 17, . . .
tabs 1,8,36-
example of using
n1,n2,...
(``arbitrary'' specification)
to set tabs at columns 1, 8, and 36.
tabs --$HOME/fspec.list/att4425-
example of using
--file
(file specification) to indicate
that tabs should be set according to the first line of
$HOME/fspec.list/att4425
[see
fspec(4)].
Errors
``UX:tabs:ERROR:illegal tabs''-
when arbitrary tabs are ordered incorrectly
``UX:tabs:ERROR:illegal increment''-
when a zero or missing increment is found in
an arbitrary specification
``UX:tabs:ERROR:unknown tab code''-
when a ``canned'' code cannot be found
``UX:tabs:ERROR:can't open''-
if --file option used, and file can't be opened
``UX:tabs:ERROR:file indirection''-
if --file option used and the specification
in that file points to yet another file.
Indirection of this form is not permitted
Files
/usr/lib/locale/locale/LC_MESSAGES/uxue-
language-specific message file [See LANG on
environ(5).]
References
environ(5),
fspec(4),
newform(1),
pr(1),
term(5),
terminfo(4),
tput(1)
Notices
There is no consistency among different terminals regarding ways of
clearing tabs and setting the left margin.
tabs
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
newform command.
For example,
tabs -8
sets every eighth position;
whereas
newform -i-8
indicates that tabs are set every eighth position.
© 2004 The SCO Group, Inc. All rights reserved.
UnixWare 7 Release 7.1.4 - 25 April 2004