Name
tr - translate or delete charactersSynopsis
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 sequence of a repeated character that is listed in the last specified SET, 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:
\eNNN character with octal value NNN (1 to 3 octal digits)
\e\e backslash
\ea audible BEL
\eb backspace
\ef form feed
\en new line
\er return
\et horizontal tab
\ev 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 the last specified SET, and occurs after translation or deletion.