expand.1 (2010 09)

e
expand(1) expand(1)
NAME
expand, unexpand - expand tabs to spaces, and vice versa
SYNOPSIS
expand [-t tablist ][file ... ]
unexpand [-a][-t tablist ][file ... ]
Obsolescent:
expand [-tabstop ][-tab1
,tab2 ,..., tabn ][file ... ]
DESCRIPTION
expand processes the named files or the standard input and writes to the standard output with tabs
changed into spaces. Backspace characters are preserved in the output, and the column count is
decreased by one column for tab calculations. For proper tab calculation, if a multi-column character is to
be "backspace’d", it should be followed by multiple backspace characters which equal to it’s column width.
If a tab character is found after the last tab position, it is replaced by a single space.
expand is useful
for preprocessing character files that contain tabs (before sorting, looking at specific columns, etc).
expand recognizes the following command-line options and arguments:
[
-t tablist ] tablist specifies where to set the tab positions instead of the default
8. tablist can
take two forms. If it is a single number, tabs are set tablist spaces apart. tablist
can also be a blank- or comma-separated list of increasing positions where tabs are
to be set.
[
-tabstop ] This option is obsolescent and is equivalent to using -t tabstop.
[
-tab1,tab2,...,tabn ]
This option is obsolescent and is equivalent to using -t tab1 ,tab2 , ... ,tabn.
unexpand processes the named files or the standard input and writes to the standard output with spaces
changed into tabs where possible. By default, only leading spaces and tabs are converted to maximal
strings of tabs. The default tab position is every 8 characters. Backspace characters are preserved into
the output, and the column count is decreased by one column for tab calculations. For proper tab calcula-
tion, if a multi-column character is to be "backspace’d", it should be followed by multiple backspace char-
acters which equal to it’s column width.
unexpand recognizes the following command-line options and arguments:
-a Tabs are inserted whenever they would compress the resultant file by replacing two
or more spaces before a tab position.
-t tablist tablist specifies the tab positions. tablist can take two forms. If it is a single
number, tabs are set every tablist spaces apart. If tablist is a blank- or comma-
separated list of increasing positions, tabs are set at those locations. The -t option
implies the -a option. If the -t option is not specified, the default is equivalent to
specifying -t 8 except that -a is not implied for this case.
EXTERNAL INFLUENCES
Environment Variables
LC_CTYPE determines the interpretation of text as single and/or multi-byte characters.
LC_MESSAGES determines the language in which messages are displayed.
If
LC_CTYPE or LC_MESSAGES is not specified in the environment or is set to the empty string, the
value of LANG is used as a default for each unspecified or empty variable. If LANG is not specified or is
set to the empty string, a default of "C" (see lang (5)) is used instead of LANG.
If any internationalization variable contains an invalid setting,
expand and unexpand behave as if all
internationalization variables are set to "C". See environ (5).
If
LC_ALL is set to a non-empty string value, it overrides the values of all the other internationalization
variables.
International Code Set Support
Single- and multi-byte character code sets are supported with the exception that
unexpand do not
recognize multi-byte alternative space characters.
HP-UX 11i Version 3: September 2010 − 1 − Hewlett-Packard Company 1