TR

Section: User Commands (1)
Updated: December 2009
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NAME

tr - translate or delete characters

SYNOPSIS

tr [OPTION]... SET1 [SET2]

DESCRIPTION

Translate, squeeze, and/or delete characters from standard input, writing to standard output.

-c, -C, --complement: use the complement of SET1
-d, --delete: delete characters in SET1, do not translate
-s, --squeeze-repeats: replace each input sequence of a repeated character that is listed in SET1 with a single occurrence of that character
-t, --truncate-set1: first truncate SET1 to length of SET2
--help: display this help and exit
--version: 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)
\\: backslash
\a: audible BEL
\b: backspace
\f: form feed
\n: new line
\r: return
\t: horizontal tab
\v: vertical tab
CHAR1-CHAR2: all characters from CHAR1 to CHAR2 in ascending order
[CHAR*]: in SET2, copies of CHAR until length of SET1
[CHAR*REPEAT]: REPEAT copies of CHAR, REPEAT octal if starting with 0
[:alnum:]: all letters and digits
[:alpha:]: all letters
[:blank:]: all horizontal whitespace
[:cntrl:]: all control characters
[:digit:]: all digits
[:graph:]: all printable characters, not including space
[:lower:]: all lower case letters
[:print:]: all printable characters, including space
[:punct:]: all punctuation characters
[:space:]: all horizontal or vertical whitespace
[:upper:]: all upper case letters
[:xdigit:]: all hexadecimal digits
[=CHAR=]: 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.

AUTHOR

Written by Jim Meyering.

REPORTING BUGS

Report tr bugs to bug-coreutils@gnu.org
GNU coreutils home page: <http://www.gnu.org/software/coreutils/>
General help using GNU software: <http://www.gnu.org/gethelp/>

COPYRIGHT

Copyright © 2009 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.