sort — sort lines of text files


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

sort [OPTION...] −−files0−from=F


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'

−h, −−human−numeric−sort

compare human readable numbers (e.g., 2K 1G)

−n, −−numeric−sort

compare according to string numerical value

−R, −−random−sort

sort by random hash of keys


get random bytes from FILE

−r, −−reverse

reverse the result of comparisons


sort according to WORD: general−numeric −g, human−numeric −h, month −M, numeric −n, random −R, version −V

−V, −−version−sort

natural sort of (version) numbers within text

Other options:


merge at most NMERGE inputs at once; for more use temp files

−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


annotate the part of the line used to sort, and warn about questionable usage to stderr


read input from the files specified by NUL−terminated names in file F; If F is − then read names from standard input

−k, −−key=POS1[,POS2]

start a key at POS1 (origin 1), end it at POS2 (default end of line). See POS syntax below

−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


change the number of sorts run concurrently to N

−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


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.


Report sort bugs to bug−

GNU coreutils home page: <>

General help using GNU software: <>

Report sort translation bugs to <>


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 coreutils 'sort invocation'

should give you access to the complete manual.


Copyright © 2011 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <>.

This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.