```

     TR(1)                                                       TR(1)

     NAME
          tr - translate characters

     SYNOPSIS
          tr [ -cds ] [ string1 [ string2 ] ]

     DESCRIPTION
          Tr copies the standard input to the standard output with
          substitution or deletion of selected characters (runes).
          Input characters found in string1 are mapped into the
          corresponding characters of string2. When string2 is short
          it is padded to the length of string1 by duplicating its
          last character.  Any combination of the options -cds may be
          used:

          -c   Complement string1: replace it with a lexicographically
               ordered list of all other characters.

          -d   Delete from input all characters in string1.

          -s   Squeeze repeated output characters that occur in
               string2 to single characters.

          In either string a noninitial sequence -x, where x is any
          character (possibly quoted), stands for a range of charac-
          ters: a possibly empty sequence of codes running from the
          successor of the previous code up through the code for x.
          The character `\' followed by 1, 2 or 3 octal digits stands
          for the character whose 16-bit value is given by those
          digits.  The character sequence `\x' followed by 1, 2, 3, or
          4 hexadecimal digits stands for the character whose 16-bit
          value is given by those digits.  A `\' followed by any other
          character stands for that character.

     EXAMPLES
          Replace all upper-case ASCII letters by lower-case.

               tr A-Z a-z <mixed >lower

          Create a list of all the words in `file1' one per line in
          `file2', where a word is taken to be a maximal string of
          alphabetics.  String2 is given as a quoted newline.

               tr -cs A-Za-z '
               ' <file1 >file2

     SOURCE
          /sys/src/cmd/tr.c

     SEE ALSO
          sed(1)

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