TABS(1) User Commands TABS(1)

NAME

tabs - set tabs on a terminal

SYNOPSIS

tabs [-n | --file
[[-code] | -a | -a2 | -c | -c2 | -c3 | -f | -p | -s | -u]]
q!! [+m [n]] [-T type]


tabs [-T type] [+ m [n]] n1 [, n2 ,...]

DESCRIPTION

The tabs utility sets the tab stops on the user's terminal according to a
tab specification, after clearing any previous settings. The user's
terminal must have remotely settable hardware tabs.

OPTIONS

The following options are supported. If a given flag occurs more than
once, the last value given takes effect:

-T type
tabs needs to know the type of terminal in order to set tabs
and margins. type is a name listed in term(7). If no -T flag
is supplied, tabs uses the value of the environment variable
TERM. If the value of TERM is NULL or TERM is not defined in
the environment (see environ(7)), tabs uses ansi+tabs as the
terminal type to provide a sequence that will work for many
terminals.


+m[n]
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 Specification

Four types of tab specification are accepted. They are described below:
canned, repetitive (-n), arbitrary (n1,n2,...), and file (-file).


If no tab specification is given, the default value is -8, that is, UNIX
system ``standard'' tabs. The lowest column number is 1. Note: 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.

Canned -code
Use one of the codes listed below to select a canned set of tabs. If more
than one code is specified, the last code option will be used. The legal
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(5)):

<: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(5)):

<: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


Repetitive
-n
A repetitive specification requests tabs at columns 1+n, 1+2*n,
etc., where n is a single-digit decimal number. 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. When -0 is used, the tab stops are cleared
and no new ones are set.


Arbitrary
See OPERANDS.

File
-file
If the name of a file is given, tabs reads the first line of the
file, searching for a format specification (see fspec(5)). 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:

example% tabs - file; pr file


Tab and margin setting is performed via the standard output.

OPERANDS

The following operand is supported:

n1[,n2,...]
The arbitrary format consists of tab-stop values
separated by commas or spaces. The tab-stop values
must be positive decimal integers 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.

EXAMPLES

Example 1: Using the tabs command

The following command is an example using -code ( canned specification)
to set tabs to the settings required by the IBM assembler: columns 1, 10,
16, 36, 72:


example% tabs -a


The next command is an 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, ...:


example% tabs -8


This command uses n1,n2,... (arbitrary specification) to set tabs at
columns 1, 8, and 36:


example% tabs 1,8,36


The last command is an 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(5)).


example% tabs -$HOME/fspec.list/att4425

ENVIRONMENT VARIABLES

See environ(7) for descriptions of the following environment variables
that affect the execution of tabs: LANG, LC_ALL, LC_CTYPE, LC_MESSAGES,
and NLSPATH.

TERM
Determine the terminal type. If this variable is unset or null,
and if the -T option is not specified, terminal type ansi+tabs
will be used.

EXIT STATUS

The following exit values are returned:

0
Successful completion.


>0
An error occurred.

ATTRIBUTES

See attributes(7) for descriptions of the following attributes:


+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|CSI | Enabled |
+--------------------+-----------------+
|Interface Stability | Standard |
+--------------------+-----------------+

SEE ALSO

expand(1), newform(1), pr(1), stty(1), tput(1), fspec(5), terminfo(5),
attributes(7), environ(7), standards(7), term(7)

NOTES

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.

February 1, 1995 TABS(1)