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Alphabetical listing for T |
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tabs(1)
NAME
tabs - Sets tab stops on terminals
SYNOPSIS
tabs [-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 standards
as follows:
tabs: XPG4, XPG4-UNIX
Refer to the standards(5) reference page for more information about
industry standards and associated tags.
OPTIONS
-n 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.
-T terminal
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.
[Compaq] If the terminal you specify is not known to the system, tabs
tries a general value that works for most terminals.
If you do not provide a -T option, tabs uses the TERM shell variable.
+mmargin
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 margin on
most terminals is defined by m0.
predefined_tab_flag
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
description of these flags.
--tab_format_file
[Compaq] 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 Specifications to use this method. The file may
contain other lines which are ignored by tabs.
Note
[Compaq] The double dash (--) format is mandatory with this option.
OPERANDS
number[,number]
Sets tabs at the named column numbers (a list in ascending order,
separated 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.
[Compaq] When you use the tabs command, always consider the leftmost
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
[Compaq] 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.
-a Sets the tabs to 1, 10, 16, 36, and 72.
-a2 Sets the tabs to 1, 10, 16, 40, and 72.
-c Sets the tabs to 1, 8, 12, 16, 20, and 55 (COBOL normal format)
-c2 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:>
[Compaq] See Format Specifications later in this reference page.
-c3 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 specification:
<:t-c3 m6 s66 d:>
-f Sets the tabs to 1, 7, 11, 15, 19, and 23 (FORTRAN).
-p Sets the tabs to 1, 5, 9, 13, 17, 21, 25, 29, 33, 37, 41, 45, 49, 53,
57, and 61 (PL/I).
-s Sets the tabs to 1, 10, and 55 (SNOBOL).
-u Sets the tabs to 1, 12, 20, and 44.
Format Specifications
[Compaq] A format specification consists of a sequence of arguments
separated by blanks and enclosed in brackets and colons: <: :>. Each
argument consists of a keyletter and an optional value which immediately
follows it. The following arguments can be used:
ttabs
[Compaq] Specifies tab settings. The value for tabs can be:
1.
[Compaq] A list of column numbers separated by commas, indicating
tab stops at the specified columns.
2.
[Compaq] A - (dash) followed by a number n, specifying tabs stops
every n columns.
3.
[Compaq] A preset tab specification, for example -a2.
ssize
[Compaq] Specifies a maximum 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.)
mmargin
[Compaq] Specifies a number of spaces to be inserted at the beginning
of each line. The margin specification must be an integer.
d [Compaq] Indicates that the line containing the format specification
is to be deleted from the converted file.
[Compaq] 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.
e [Compaq] Indicates that the current format should prevail only until
another format specification is encountered in the file.
[Compaq] Default values of t-8 and m0 are assumed if t and m arguments 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
1. The tabs command assumes that standard output is the terminal. If
standard output is redirected, the results are unpredicable.
2. Full operation of all capabilities may be restricted by the hardware.
EXIT STATUS
The following exit values are returned:
0 Successful completion.
>0 An error occurred.
EXAMPLES
1. To set tabs every four spaces, enter:
tabs -4
2. To clear all tabs, enter:
tabs
ENVIRONMENT VARIABLES
The following environment variables affect the execution of tabs:
LANG
Provides 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
variables contain an invalid setting, the utility behaves as if none of
the variables had been defined.
LC_ALL
If set to a non-empty string value, overrides the values of all the
other internationalization variables.
LC_CTYPE
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).
LC_MESSAGES
Determines the locale for the format and contents of diagnostic
messages written to standard error.
NLSPATH
Determines the location of message catalogues for the processing of
LC_MESSAGES.
TERM
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)