tr [OPTION]... SET1 [SET2]
Translate, squeeze, and/or delete characters from standard input, writ-
ing to standard output.
-c, -C, --complement
first complement SET1
delete characters in SET1, do not translate
replace each input sequence of a repeated character that is
listed in SET1 with a single occurrence of that character
first truncate SET1 to length of SET2
--help display this help and exit
output version information and exit
SETs are specified as strings of characters. Most represent them-
selves. Interpreted sequences are:
\NNN character with octal value NNN (1 to 3 octal digits)
\a audible BEL
\f form feed
\n new line
\t horizontal tab
\v vertical tab
all characters from CHAR1 to CHAR2 in ascending order
in SET2, copies of CHAR until length of SET1
all printable characters, not including space
all lower case letters
all printable characters, including space
all punctuation characters
all horizontal or vertical whitespace
all upper case letters
all hexadecimal digits
all characters which are equivalent to CHAR
Translation occurs if -d is not given and both SET1 and SET2 appear.
-t may be used only when translating. SET2 is extended to length of
SET1 by repeating its last character as necessary. Excess characters
of SET2 are ignored. Only [:lower:] and [:upper:] are guaranteed to
expand in ascending order; used in SET2 while translating, they may
only be used in pairs to specify case conversion. -s uses SET1 if not
translating nor deleting; else squeezing uses SET2 and occurs after
translation or deletion.
Written by Jim Meyering.
Report bugs to <email@example.com>.
Copyright (C) 2006 Free Software Foundation, Inc.
This is free software. You may redistribute copies of it under the
terms of the GNU General Public License
<http://www.gnu.org/licenses/gpl.html>. There is NO WARRANTY, to the
extent permitted by law.
The full documentation for tr is maintained as a Texinfo manual. If