TR(1) User Commands TR(1)

tr - translate or delete characters

tr [OPTION]... STRING1 [STRING2]

Translate, squeeze, and/or delete characters from standard input, writing to standard output. STRING1 and STRING2 specify arrays of characters ARRAY1 and ARRAY2 that control the action.

use the complement of ARRAY1
delete characters in ARRAY1, do not translate
replace each sequence of a repeated character that is listed in the last specified ARRAY, with a single occurrence of that character
-t, --truncate-set1
first truncate ARRAY1 to length of ARRAY2
display this help and exit
output version information and exit

ARRAYs are specified as strings of characters. Most represent themselves. Interpreted sequences are:

character with octal value NNN (1 to 3 octal digits)
\\
backslash
audible BEL
backspace
form feed
new line
return
horizontal tab
vertical tab
all characters from CHAR1 to CHAR2 in ascending order
[CHAR*]
in ARRAY2, copies of CHAR until length of ARRAY1
[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 STRING1 and STRING2 appear. -t may be used only when translating. ARRAY2 is extended to length of ARRAY1 by repeating its last character as necessary. Excess characters of ARRAY2 are ignored. Character classes expand in unspecified order; while translating, [:lower:] and [:upper:] may be used in pairs to specify case conversion. Squeezing occurs after translation or deletion.

Full support is available only for safe single-byte locales, in which every possible input byte represents a single character. The C locale is safe in GNU systems, so you can avoid this issue in the shell by running LC_ALL=C tr instead of plain tr.

Written by Jim Meyering.

GNU coreutils online help: https://www.gnu.org/software/coreutils/
Report any translation bugs to https://translationproject.org/team/

Copyright © 2022 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later https://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.

Full documentation https://www.gnu.org/software/coreutils/tr
or available locally via: info '(coreutils) tr invocation'

April 2022 GNU coreutils 9.1