EXPAND(1) | General Commands Manual | EXPAND(1) |
expand
, unexpand
— expand tabs to spaces, and vice versa
expand |
[-t tablist]
[file ...] |
unexpand |
[-a ] [file ...] |
expand
processes the named files or the
standard input, writing the standard output with tabs changed into blanks.
Backspace characters are preserved into the output and decrement the column
count for tab calculations. expand
is useful for
pre-processing character files (before sorting, looking at specific columns,
etc.) that contain tabs.
unexpand
puts tabs back into the data from
the standard input or the named files and writes the result on the standard
output.
The options are as follows:
-a
-a
option is given, tabs
are inserted whenever they would compress the resultant file by replacing
two or more characters.-t
tablist-t
,
tablist, consists of a single numerical argument,
tabs are set tablist spaces apart instead of the
default 8. If multiple -t
options are given, then
the tabs are set at those specific columns.
Otherwise the argument to -t
may
consist of a list of two or more positive decimal integers, separated by
commas or single blank characters, in ascending order: in the event of
having to process a ⟨tab⟩ at a position beyond the last of
those specified in a multiple -t
list, the
⟨tab⟩ is replaced by a single ⟨space⟩
character.
This implementation of expand
additionally allows tablist to be specified
without using the -t
flag, by prefixing
tablist with a dash (-).
The expand
and
unexpand
utilities exit 0 on success,
and >0 if an error occurs.
The expand
and
unexpand
utilities are compliant with the
IEEE Std 1003.1-2008 (“POSIX.1”)
specification, except that this implementation does not support a
-t
flag for unexpand
.
The ability to specify tabstops without the
-t
flag is not specified by IEEE
Std 1003.1-2008 (“POSIX.1”), though it states it
“may be present in some implementations”.
The expand
utility first appeared in
1BSD.
March 17, 2014 | OpenBSD-current |