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Linux / Unix Command: tr
Command Library


tr - translate or delete characters  


tr [OPTION]... SET1 [SET2]  


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

-c, --complement
first complement 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
display this help and exit
output version information and exit

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

character with octal value NNN (1 to 3 octal digits)
audible BEL
form feed
new line
horizontal tab
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 letters
all horizontal whitespace
all control characters
all digits
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.  


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 tr

should give you access to the complete manual.

Important: Use the man command (% man) to see how a command is used on your particular computer.

>> Linux/Unix Command Library

>> Shell Command Library

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