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sort - sort lines of text files


sort [OPTION]... [FILE]...


Write sorted concatenation of all FILE(s) to standard output.

Mandatory arguments to long options are mandatory for short options too. Ordering options:

-b, --ignore-leading-blanks
ignore leading blanks

-d, --dictionary-order
consider only blanks and alphanumeric characters

-f, --ignore-case
fold lower case to upper case characters

-g, --general-numeric-sort
compare according to general numerical value

-i, --ignore-nonprinting
consider only printable characters

-M, --month-sort
compare (unknown) < ‘JAN’ < ... < ‘DEC’

-n, --numeric-sort
compare according to string numerical value

-R, --random-sort
sort by random hash of keys

get random bytes from FILE (default /dev/urandom)

-r, --reverse
reverse the result of comparisons

Other options:

-c, --check, --check=diagnose-first
check for sorted input; do not sort

-C, --check=quiet, --check=silent
like -c, but do not report first bad line

compress temporaries with PROG; decompress them with PROG -d

-k, --key=POS1[,POS2]
start a key at POS1, end it at POS2 (origin 1)

-m, --merge
merge already sorted files; do not sort

-o, --output=FILE
write result to FILE instead of standard output

-s, --stable
stabilize sort by disabling last-resort comparison

-S, --buffer-size=SIZE
use SIZE for main memory buffer

-t, --field-separator=SEP
use SEP instead of non-blank to blank transition

-T, --temporary-directory=DIR
use DIR for temporaries, not $TMPDIR or /tmp; multiple options specify multiple directories

-u, --unique
with -c, check for strict ordering; without -c, output only the first of an equal run

-z, --zero-terminated
end lines with 0 byte, not newline

--help display this help and exit

output version information and exit

POS is F[.C][OPTS], where F is the field number and C the character position in the field; both are origin 1. If neither -t nor -b is in effect, characters in a field are counted from the beginning of the preceding whitespace. OPTS is one or more single-letter ordering options, which override global ordering options for that key. If no key is given, use the entire line as the key.

SIZE may be followed by the following multiplicative suffixes: % 1% of memory, b 1, K 1024 (default), and so on for M, G, T, P, E, Z, Y.

With no FILE, or when FILE is -, read standard input.

*** WARNING *** The locale specified by the environment affects sort order. Set LC_ALL=C to get the traditional sort order that uses native byte values.


Written by Mike Haertel and Paul Eggert.

Reporting Bugs

Report bugs to <>.


Copyright © 2007 Free Software Foundation, Inc. This is free software. You may redistribute copies of it under the terms of the GNU General Public License <>. There is NO WARRANTY, to the extent permitted by law.

See Also

The full documentation for sort is maintained as a Texinfo manual. If the info and sort programs are properly installed at your site, the command

info sort

should give you access to the complete manual.

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use open software!