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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 sequence of characters with one |
?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) |
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\\ |
backslash |
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\a |
audible BEL |
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\b |
backspace |
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\f |
form feed |
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\n |
new line |
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\r |
return |
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\t |
horizontal tab |
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\v |
vertical tab |
CHAR1-CHAR2 |
all characters from CHAR1 to CHAR2 in ascending order |
[CHAR1-CHAR2] |
same as CHAR1-CHAR2, if both SET1 and SET2 use this |
[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. |
Written by Jim Meyering. |
Report bugs to <bug-textutils@gnu.org>. |
Copyright © 1999 Free Software Foundation, Inc. |
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. |