Check out perldoc perlop for the options to tr. As it appears our site docs are still a bit old, here is an excerpt from a Perl5.6.0 dist: 
c   Complement the SEARCHLIST.
d   Delete found but unreplaced characters.
s   Squash duplicate replaced characters.
U   Translate to/from UTF-8.
C   Translate to/from 8-bit char (octet).

jeffa

In reply to (jeffa) 3Re: problems with tr///; by jeffa
in thread problems with tr///; by Anonymous Monk

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