SORT(1)                                                   SORT(1)

     NAME
          sort - sort and/or merge files

     SYNOPSIS
          sort [ -cmuMbdfinrtx ] [ +pos1 [ -pos2 ] ] ... [ -o output ]
          [ -ymemory ] [ -zrecsize ] [ names ]

     DESCRIPTION
          Sort sorts lines of all the named files together and writes
          the result on the standard output.  The name - means the
          standard input.  If no input files are named, the standard
          input is sorted.

          The default sort key is an entire line.  Default ordering is
          lexicographic by bytes in machine collating sequence.  The
          ordering is affected globally by the following options, one
          or more of which may appear.

          M    Compare as months.  The first three non-blank charac-
               ters of the field are folded to lower case and compared
               so that `jan' < `feb' < ... < `dec'.  Invalid fields
               compare low to `jan'.

          b    Ignore leading blanks (spaces and tabs) in field com-
               parisons.

          d    `Dictionary' order: only letters, digits and blanks are
               significant in comparisons.

          f    Fold upper case letters onto lower case.

          i    Ignore characters outside the ASCII range 040-0176 in
               non-numeric comparisons.

          n    An initial numeric string, consisting of optional
               blanks, optional minus sign, and zero or more digits
               with optional decimal point, is sorted by arithmetic
               value.  Option n implies option b.

          r    Reverse the sense of comparisons.

          tx   `Tab character' separating fields is x.

          The notation +pos1 -pos2 restricts a sort key to a field
          beginning at pos1 and ending just before pos2. Pos1 and pos2
          each have the form m.n, optionally followed by one or more
          of the flags Mbdfinr, where m tells a number of fields to
          skip from the beginning of the line and n tells a number of
          characters to skip further.  If any flags are present they
          override all the global ordering options for this key.  If

     SORT(1)                                                   SORT(1)

          the b option is in effect n is counted from the first non-
          blank in the field; b is attached independently to pos2. A
          missing .n means .0; a missing -pos2 means the end of the
          line.  Under the -tx option, fields are strings separated by
          x; otherwise fields are non-empty non-blank strings sepa-
          rated by blanks.  The blanks separating fields are consid-
          ered the first characters in the field.

          When there are multiple sort keys, later keys are compared
          only after all earlier keys compare equal.  Lines that oth-
          erwise compare equal are ordered with all bytes significant.

          These option arguments are also understood:

          c    Check that the single input file is sorted according to
               the ordering rules; give no output unless the file is
               out of sort.

          m    Merge only, the input files are already sorted.

          u    Suppress all but one in each set of equal lines.
               Ignored bytes and bytes outside keys do not participate
               in this comparison.

          o    The next argument is the name of an output file to use
               instead of the standard output.  This file may be the
               same as one of the inputs.

          ymemory
               Suggests the use of the specified number of bytes of
               internal store in hopes of tuning performance; 0 is
               appropriate for very small files, a missing number for
               huge ones.

          zrecsize
               provide for abnormally large records; useful only with
               -c and -m

     EXAMPLES
          sort -u +0f +0 list
               Print in alphabetical order all the unique spellings in
               a list of words where capitalized words differ from
               uncapitalized.

          sort -t: +2n /etc/passwd
               Print the password file (passwd(5)) sorted by userid
               (the third colon-separated field).

          sort -umM dates
               Print the first instance of each month in an already
               sorted file.  Options -um with just one input file make
               the choice of a unique representative from a set of

     SORT(1)                                                   SORT(1)

               equal lines predictable.

     FILES
          /usr/tmp/stm???

     SEE ALSO
          comm(1), join(1), uniq(1).

     DIAGNOSTICS
          Comments and exits with non-zero status for various trouble
          conditions and for disorder discovered under option -c.