NAME

     tr - translate character codes


SYNOPSIS

     tr [-cds] [string1] [string2]


OPTIONS

     -c   Complement the set of characters in string1

     -d   Delete all characters specified in string1

     -s   Squeeze all runs of characters in string1 to one  char-
          acter


EXAMPLES

     tr 'A-Z' 'a-z' <x >y
                         # Convert upper case to lower case

     tr -d '0123456789' <f1 >f2
                         # Delete all digits from f1


DESCRIPTION

     Tr performs simple character translation.  When no  flag  is
     specified,  each  character  in  string1  is mapped onto the
     corresponding character in string2 .

     There are two types of tr out there, one that requires [ and
     ]  for  character  classes,  and one that does not.  Here is
     what the example above would look like for a tr  that  needs
     the brackets:

          tr '[A-Z]' '[a-z]' <x >y

     Use [ and ] if you want to be portable, because  a  tr  that
     doesn't  need  them  will  still accept the syntax and mind-
     lessly translate [ into [ and ] into ].