sort - sort a file of ASCII lines

     sort [-bcdfimnru] [-tc]  [-o name] [+pos1] [-pos2] file ...


     -b   Skip leading blanks when making comparisons

     -c   Check to see if a file is sorted

     -d   Dictionary order: ignore punctuation

     -f   Fold upper case onto lower case

     -i   Ignore nonASCII characters

     -m   Merge presorted files

     -n   Numeric sort order

     -o   Next argument is output file

     -r   Reverse the sort order

     -t   Following character is field separator

     -u   Unique mode (delete duplicate lines)


     sort -nr file       # Sort keys numerically, reversed

     sort +2 -4 file     # Sort using fields 2 and 3 as key

     sort +2 -t: -o out  # Field separator is :

     sort +.3 -.6        # Characters 3 through 5 form the key


     Sort sorts one or more files.   If  no  files  are  specified,  stdin  is
     sorted.   Output  is  written on standard output, unless -o is specified.
     The options +pos1 -pos2 use only fields pos1 up to but not including pos2
     as  the  sort  key,  where a field is a string of characters delimited by
     spaces and tabs, unless a different field delimiter is specified with -t.
     Both  pos1  and pos2 have the form m.n where m tells the number of fields
     and n tells the number of characters.  Either m or n may be omitted.

     comm(1), grep(1), uniq(1).