xref: /freebsd/usr.bin/tr/tr.1 (revision 282a3889ebf826db9839be296ff1dd903f6d6d6e)
1.\" Copyright (c) 1991, 1993
2.\"	The Regents of the University of California.  All rights reserved.
3.\"
4.\" This code is derived from software contributed to Berkeley by
5.\" the Institute of Electrical and Electronics Engineers, Inc.
6.\"
7.\" Redistribution and use in source and binary forms, with or without
8.\" modification, are permitted provided that the following conditions
9.\" are met:
10.\" 1. Redistributions of source code must retain the above copyright
11.\"    notice, this list of conditions and the following disclaimer.
12.\" 2. Redistributions in binary form must reproduce the above copyright
13.\"    notice, this list of conditions and the following disclaimer in the
14.\"    documentation and/or other materials provided with the distribution.
15.\" 3. All advertising materials mentioning features or use of this software
16.\"    must display the following acknowledgement:
17.\"	This product includes software developed by the University of
18.\"	California, Berkeley and its contributors.
19.\" 4. Neither the name of the University nor the names of its contributors
20.\"    may be used to endorse or promote products derived from this software
21.\"    without specific prior written permission.
22.\"
23.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33.\" SUCH DAMAGE.
34.\"
35.\"     @(#)tr.1	8.1 (Berkeley) 6/6/93
36.\" $FreeBSD$
37.\"
38.Dd October 13, 2006
39.Dt TR 1
40.Os
41.Sh NAME
42.Nm tr
43.Nd translate characters
44.Sh SYNOPSIS
45.Nm
46.Op Fl Ccsu
47.Ar string1 string2
48.Nm
49.Op Fl Ccu
50.Fl d
51.Ar string1
52.Nm
53.Op Fl Ccu
54.Fl s
55.Ar string1
56.Nm
57.Op Fl Ccu
58.Fl ds
59.Ar string1 string2
60.Sh DESCRIPTION
61The
62.Nm
63utility copies the standard input to the standard output with substitution
64or deletion of selected characters.
65.Pp
66The following options are available:
67.Bl -tag -width Ds
68.It Fl C
69Complement the set of characters in
70.Ar string1 ,
71that is
72.Dq Fl C Li ab
73includes every character except for
74.Ql a
75and
76.Ql b .
77.It Fl c
78Same as
79.Fl C
80but complement the set of values in
81.Ar string1 .
82.It Fl d
83Delete characters in
84.Ar string1
85from the input.
86.It Fl s
87Squeeze multiple occurrences of the characters listed in the last
88operand (either
89.Ar string1
90or
91.Ar string2 )
92in the input into a single instance of the character.
93This occurs after all deletion and translation is completed.
94.It Fl u
95Guarantee that any output is unbuffered.
96.El
97.Pp
98In the first synopsis form, the characters in
99.Ar string1
100are translated into the characters in
101.Ar string2
102where the first character in
103.Ar string1
104is translated into the first character in
105.Ar string2
106and so on.
107If
108.Ar string1
109is longer than
110.Ar string2 ,
111the last character found in
112.Ar string2
113is duplicated until
114.Ar string1
115is exhausted.
116.Pp
117In the second synopsis form, the characters in
118.Ar string1
119are deleted from the input.
120.Pp
121In the third synopsis form, the characters in
122.Ar string1
123are compressed as described for the
124.Fl s
125option.
126.Pp
127In the fourth synopsis form, the characters in
128.Ar string1
129are deleted from the input, and the characters in
130.Ar string2
131are compressed as described for the
132.Fl s
133option.
134.Pp
135The following conventions can be used in
136.Ar string1
137and
138.Ar string2
139to specify sets of characters:
140.Bl -tag -width [:equiv:]
141.It character
142Any character not described by one of the following conventions
143represents itself.
144.It \eoctal
145A backslash followed by 1, 2 or 3 octal digits represents a character
146with that encoded value.
147To follow an octal sequence with a digit as a character, left zero-pad
148the octal sequence to the full 3 octal digits.
149.It \echaracter
150A backslash followed by certain special characters maps to special
151values.
152.Pp
153.Bl -column "\ea"
154.It "\ea	<alert character>
155.It "\eb	<backspace>
156.It "\ef	<form-feed>
157.It "\en	<newline>
158.It "\er	<carriage return>
159.It "\et	<tab>
160.It "\ev	<vertical tab>
161.El
162.Pp
163A backslash followed by any other character maps to that character.
164.It c-c
165For non-octal range endpoints
166represents the range of characters between the range endpoints, inclusive,
167in ascending order,
168as defined by the collation sequence.
169If either or both of the range endpoints are octal sequences, it
170represents the range of specific coded values between the
171range endpoints, inclusive.
172.Pp
173.Bf Em
174See the
175.Sx COMPATIBILITY
176section below for an important note regarding
177differences in the way the current
178implementation interprets range expressions differently from
179previous implementations.
180.Ef
181.It [:class:]
182Represents all characters belonging to the defined character class.
183Class names are:
184.Pp
185.Bl -column "phonogram"
186.It "alnum	<alphanumeric characters>
187.It "alpha	<alphabetic characters>
188.It "blank	<whitespace characters>
189.It "cntrl	<control characters>
190.It "digit	<numeric characters>
191.It "graph	<graphic characters>
192.It "ideogram	<ideographic characters>
193.It "lower	<lower-case alphabetic characters>
194.It "phonogram	<phonographic characters>
195.It "print	<printable characters>
196.It "punct	<punctuation characters>
197.It "rune	<valid characters>
198.It "space	<space characters>
199.It "special	<special characters>
200.It "upper	<upper-case characters>
201.It "xdigit	<hexadecimal characters>
202.El
203.Pp
204.\" All classes may be used in
205.\" .Ar string1 ,
206.\" and in
207.\" .Ar string2
208.\" when both the
209.\" .Fl d
210.\" and
211.\" .Fl s
212.\" options are specified.
213.\" Otherwise, only the classes ``upper'' and ``lower'' may be used in
214.\" .Ar string2
215.\" and then only when the corresponding class (``upper'' for ``lower''
216.\" and vice-versa) is specified in the same relative position in
217.\" .Ar string1 .
218.\" .Pp
219When
220.Dq Li [:lower:]
221appears in
222.Ar string1
223and
224.Dq Li [:upper:]
225appears in the same relative position in
226.Ar string2 ,
227it represents the characters pairs from the
228.Dv toupper
229mapping in the
230.Ev LC_CTYPE
231category of the current locale.
232When
233.Dq Li [:upper:]
234appears in
235.Ar string1
236and
237.Dq Li [:lower:]
238appears in the same relative position in
239.Ar string2 ,
240it represents the characters pairs from the
241.Dv tolower
242mapping in the
243.Ev LC_CTYPE
244category of the current locale.
245.Pp
246With the exception of case conversion,
247characters in the classes are in unspecified order.
248.Pp
249For specific information as to which
250.Tn ASCII
251characters are included
252in these classes, see
253.Xr ctype 3
254and related manual pages.
255.It [=equiv=]
256Represents all characters belonging to the same equivalence class as
257.Ar equiv ,
258ordered by their encoded values.
259.It [#*n]
260Represents
261.Ar n
262repeated occurrences of the character represented by
263.Ar # .
264This
265expression is only valid when it occurs in
266.Ar string2 .
267If
268.Ar n
269is omitted or is zero, it is be interpreted as large enough to extend
270.Ar string2
271sequence to the length of
272.Ar string1 .
273If
274.Ar n
275has a leading zero, it is interpreted as an octal value, otherwise,
276it is interpreted as a decimal value.
277.El
278.Sh ENVIRONMENT
279The
280.Ev LANG , LC_ALL , LC_CTYPE
281and
282.Ev LC_COLLATE
283environment variables affect the execution of
284.Nm
285as described in
286.Xr environ 7 .
287.Sh EXIT STATUS
288.Ex -std
289.Sh EXAMPLES
290The following examples are shown as given to the shell:
291.Pp
292Create a list of the words in file1, one per line, where a word is taken to
293be a maximal string of letters.
294.Pp
295.D1 Li "tr -cs \*q[:alpha:]\*q \*q\en\*q < file1"
296.Pp
297Translate the contents of file1 to upper-case.
298.Pp
299.D1 Li "tr \*q[:lower:]\*q \*q[:upper:]\*q < file1"
300.Pp
301(This should be preferred over the traditional
302.Ux
303idiom of
304.Dq Li "tr a-z A-Z" ,
305since it works correctly in all locales.)
306.Pp
307Strip out non-printable characters from file1.
308.Pp
309.D1 Li "tr -cd \*q[:print:]\*q < file1"
310.Pp
311Remove diacritical marks from all accented variants of the letter
312.Ql e :
313.Pp
314.Dl "tr \*q[=e=]\*q \*qe\*q"
315.Sh COMPATIBILITY
316Previous
317.Fx
318implementations of
319.Nm
320did not order characters in range expressions according to the current
321locale's collation order, making it possible to convert unaccented Latin
322characters (esp.\& as found in English text) from upper to lower case using
323the traditional
324.Ux
325idiom of
326.Dq Li "tr A-Z a-z" .
327Since
328.Nm
329now obeys the locale's collation order, this idiom may not produce
330correct results when there is not a 1:1 mapping between lower and
331upper case, or when the order of characters within the two cases differs.
332As noted in the
333.Sx EXAMPLES
334section above, the character class expressions
335.Dq Li [:lower:]
336and
337.Dq Li [:upper:]
338should be used instead of explicit character ranges like
339.Dq Li a-z
340and
341.Dq Li A-Z .
342.Pp
343System V has historically implemented character ranges using the syntax
344.Dq Li [c-c]
345instead of the
346.Dq Li c-c
347used by historic
348.Bx
349implementations and
350standardized by POSIX.
351System V shell scripts should work under this implementation as long as
352the range is intended to map in another range, i.e., the command
353.Dq Li "tr [a-z] [A-Z]"
354will work as it will map the
355.Ql \&[
356character in
357.Ar string1
358to the
359.Ql \&[
360character in
361.Ar string2 .
362However, if the shell script is deleting or squeezing characters as in
363the command
364.Dq Li "tr -d [a-z]" ,
365the characters
366.Ql \&[
367and
368.Ql \&]
369will be
370included in the deletion or compression list which would not have happened
371under a historic System V implementation.
372Additionally, any scripts that depended on the sequence
373.Dq Li a-z
374to
375represent the three characters
376.Ql a ,
377.Ql \-
378and
379.Ql z
380will have to be
381rewritten as
382.Dq Li a\e-z .
383.Pp
384The
385.Nm
386utility has historically not permitted the manipulation of NUL bytes in
387its input and, additionally, stripped NUL's from its input stream.
388This implementation has removed this behavior as a bug.
389.Pp
390The
391.Nm
392utility has historically been extremely forgiving of syntax errors,
393for example, the
394.Fl c
395and
396.Fl s
397options were ignored unless two strings were specified.
398This implementation will not permit illegal syntax.
399.Sh STANDARDS
400The
401.Nm
402utility conforms to
403.St -p1003.1-2001 .
404The
405.Dq ideogram ,
406.Dq phonogram ,
407.Dq rune ,
408and
409.Dq special
410character classes are extensions.
411.Pp
412It should be noted that the feature wherein the last character of
413.Ar string2
414is duplicated if
415.Ar string2
416has less characters than
417.Ar string1
418is permitted by POSIX but is not required.
419Shell scripts attempting to be portable to other POSIX systems should use
420the
421.Dq Li [#*]
422convention instead of relying on this behavior.
423The
424.Fl u
425option is an extension to the
426.St -p1003.1-2001
427standard.
428