tr - translate or delete characters
tr [OPTION]... SET1 [SET2]
Translate, squeeze, and/or delete characters from standard input, writing to standard output.
-c, -C, --complement
use the complement of 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 themselves. 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
REPEAT copies of CHAR, REPEAT octal if starting with 0
all letters and digits
all horizontal whitespace
all control characters
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 tr bugs to firstname.lastname@example.org
GNU coreutils home page: <http://www.gnu.org/software/coreutils/>
General help using GNU software: <http://www.gnu.org/gethelp/>
Report tr translation bugs to <http://translationproject.org/team/>
Copyright © 2013 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.
The full documentation for tr is maintained as a Texinfo manual. If the info and tr programs are properly installed at your site, the command
info coreutils 'tr invocation'
should give you access to the complete manual.