sort linux command

sort

sort [options] [files]

Sort the lines of the named files. Compare specified fields for each pair of lines, or, if no fields are specified, compare them by byte, in machine collating sequence. See also uniq, comm, and join.

Options

-b

Ignore leading spaces and tabs.

-c

Check whether files are already sorted, and, if so, produce no output.

-d

Sort in dictionary order.

-f

Fold -- ignore uppercase/lowercase differences.

--help

Print a help message and then exit.

-i

Ignore nonprinting characters (those outside ASCII range 040-176).

-m

Merge (i.e., sort as a group) input files.

-n

Sort in arithmetic order.

-ofile

Put output in file.

-r

Reverse the order of the sort.

-tc

Separate fields with c (default is a tab).

-u

Identical lines in input file appear only one (unique) time in output.

-zrecsz

Provide recsz bytes for any one line in the file. This option prevents abnormal termination of sort in certain cases.

n m

Skip n fields before sorting, and sort up to field position m. If m is missing, sort to end of line. Positions take the form a.b, which means character b of field a. If .b is missing, sort at the first character of the field.

-k n m

Similar to +. Skip n-1 fields and stop at m-1 fields (i.e., start sorting at the nth field, where the fields are numbered beginning with 1).

--version

Print version information and then exit.

-M

Attempt to treat the first three characters as a month designation (JAN, FEB, etc.). In comparisons, treat JAN < FEB and any valid month as less than an invalid name for a month.

-T tempdir

Directory pathname to be used for temporary files.

Examples

List files by decreasing number of lines:

Alphabetize a list of words, remove duplicates, and print the frequency of each word:

Sort the password file numerically by the third field (user ID):