Sort is a standard Unix command line program that prints the lines of its input or concatenation of all files listed in its argument list in sorted order. Sorting is done based on one or more sort keys extracted from each line of input. By default, the entire input is taken as sort key. Blank space is taken used as default field separator. The -r flag will reverse the sort order.

Examples

Sort the current directory by file size

$ls -s | sort -n
  96 Nov1.txt
 128 _arch_backup.lst
 128 _arch_backup.lst.tmp
1708 NMON

Sort a file in alpha order

 $ cat phonebook
 Smith, Brett     555-4321
 Doe, John        555-1234
 Doe, Jane        555-3214
 Avery, Cory      555-4321
 Fogarty, Suzie   555-2314
   
 $ sort phonebook
 Avery, Cory      555-4321
 Doe, Jane        555-3214
 Doe, John        555-1234
 Fogarty, Suzie   555-2314
 Smith, Brett     555-4321

Sort by number

The -n option makes the program sort according to numerical value:

 $ du /bin/* | sort -n
 4       /bin/domainname
 24      /bin/ls
 102     /bin/sh
 304     /bin/csh

In old versions of sort, the +1 option made the program sort using the second column of data (+2 for the third, etc.). This is no longer supported, and instead the -k option can be used to do the same thing (note: "-k 2" for the second column):

 $ cat zipcode
 Adam  12345
 Bob   34567
 Joe   56789
 Sam   45678
 Wendy 23456
   
 $ sort -nk 2 zipcode
 Adam  12345
 Wendy 23456
 Bob   34567
 Sam   45678
 Joe   56789

Sorting a pipe delimited file

 $ sort -t'|' -k2 zipcode
 Adam|12345
 Wendy|23456
 Bob|34567
 Sam|45678
 Joe|56789

Sort in reverse

The -r option just reverses the order of the sort:

 $ sort -nrk 2 zipcode
 Joe   56789
 Sam   45678
 Bob   34567
 Wendy 23456
 Adam  12345

See also

• Collation
• List of Unix programs

External links

• [1] The program's manpage
• Softpanorama Unix sort page
• Online interface to the sort program

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