c18d8171a6
Reviewed by: cpercival MFC after: 1 week
177 lines
4.7 KiB
Groff
177 lines
4.7 KiB
Groff
.\" Copyright (c) 1998 Softweyr LLC. All rights reserved.
|
|
.\"
|
|
.\" strtok_r, from Berkeley strtok
|
|
.\" Oct 13, 1998 by Wes Peters <wes@softweyr.com>
|
|
.\"
|
|
.\" Copyright (c) 1988, 1991, 1993
|
|
.\" The Regents of the University of California. All rights reserved.
|
|
.\"
|
|
.\" This code is derived from software contributed to Berkeley by
|
|
.\" the American National Standards Committee X3, on Information
|
|
.\" Processing Systems.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\"
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notices, this list of conditions and the following disclaimer.
|
|
.\"
|
|
.\" 2. Redistributions in binary form must reproduce the above
|
|
.\" copyright notices, this list of conditions and the following
|
|
.\" disclaimer in the documentation and/or other materials provided
|
|
.\" with the distribution.
|
|
.\"
|
|
.\" 3. Neither the name of Softweyr LLC, the University nor the names
|
|
.\" of its contributors may be used to endorse or promote products
|
|
.\" derived from this software without specific prior written
|
|
.\" permission.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY SOFTWEYR LLC, THE REGENTS AND
|
|
.\" CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
|
|
.\" INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
|
|
.\" MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
|
.\" DISCLAIMED. IN NO EVENT SHALL SOFTWEYR LLC, THE REGENTS, OR
|
|
.\" CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
|
.\" SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
|
.\" LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
|
|
.\" USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
|
|
.\" ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
|
|
.\" OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
|
|
.\" OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" @(#)strtok.3 8.2 (Berkeley) 2/3/94
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd January 22, 2016
|
|
.Dt STRTOK 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm strtok , strtok_r
|
|
.Nd string tokens
|
|
.Sh LIBRARY
|
|
.Lb libc
|
|
.Sh SYNOPSIS
|
|
.In string.h
|
|
.Ft char *
|
|
.Fn strtok "char *str" "const char *sep"
|
|
.Ft char *
|
|
.Fn strtok_r "char *str" "const char *sep" "char **last"
|
|
.Sh DESCRIPTION
|
|
.Bf -symbolic
|
|
This interface is obsoleted by
|
|
.Xr strsep 3 .
|
|
.Ef
|
|
.Pp
|
|
The
|
|
.Fn strtok
|
|
function
|
|
is used to isolate sequential tokens in a null-terminated string,
|
|
.Fa str .
|
|
These tokens are separated in the string by at least one of the
|
|
characters in
|
|
.Fa sep .
|
|
The first time that
|
|
.Fn strtok
|
|
is called,
|
|
.Fa str
|
|
should be specified; subsequent calls, wishing to obtain further tokens
|
|
from the same string, should pass a null pointer instead.
|
|
The separator string,
|
|
.Fa sep ,
|
|
must be supplied each time, and may change between calls.
|
|
.Pp
|
|
The implementation will behave as if no library function calls
|
|
.Fn strtok .
|
|
.Pp
|
|
The
|
|
.Fn strtok_r
|
|
function is a reentrant version of
|
|
.Fn strtok .
|
|
The context pointer
|
|
.Fa last
|
|
must be provided on each call.
|
|
The
|
|
.Fn strtok_r
|
|
function
|
|
may also be used to nest two parsing loops within one another, as
|
|
long as separate context pointers are used.
|
|
.Pp
|
|
The
|
|
.Fn strtok
|
|
and
|
|
.Fn strtok_r
|
|
functions
|
|
return a pointer to the beginning of each subsequent token in the string,
|
|
after replacing the token itself with a
|
|
.Dv NUL
|
|
character.
|
|
When no more tokens remain, a null pointer is returned.
|
|
.Sh EXAMPLES
|
|
The following uses
|
|
.Fn strtok_r
|
|
to parse two strings using separate contexts:
|
|
.Bd -literal
|
|
char test[80], blah[80];
|
|
char *sep = "\e\e/:;=-";
|
|
char *word, *phrase, *brkt, *brkb;
|
|
|
|
strcpy(test, "This;is.a:test:of=the/string\e\etokenizer-function.");
|
|
|
|
for (word = strtok_r(test, sep, &brkt);
|
|
word;
|
|
word = strtok_r(NULL, sep, &brkt))
|
|
{
|
|
strcpy(blah, "blah:blat:blab:blag");
|
|
|
|
for (phrase = strtok_r(blah, sep, &brkb);
|
|
phrase;
|
|
phrase = strtok_r(NULL, sep, &brkb))
|
|
{
|
|
printf("So far we're at %s:%s\en", word, phrase);
|
|
}
|
|
}
|
|
.Ed
|
|
.Sh SEE ALSO
|
|
.Xr memchr 3 ,
|
|
.Xr strchr 3 ,
|
|
.Xr strcspn 3 ,
|
|
.Xr strpbrk 3 ,
|
|
.Xr strrchr 3 ,
|
|
.Xr strsep 3 ,
|
|
.Xr strspn 3 ,
|
|
.Xr strstr 3 ,
|
|
.Xr wcstok 3
|
|
.Sh STANDARDS
|
|
The
|
|
.Fn strtok
|
|
function
|
|
conforms to
|
|
.St -isoC .
|
|
The
|
|
.Fn strtok_r
|
|
function
|
|
conforms to
|
|
.St -p1003.1-2001 .
|
|
.Sh AUTHORS
|
|
.An Wes Peters Aq Mt wes@softweyr.com ,
|
|
Softweyr LLC
|
|
.Pp
|
|
Based on the
|
|
.Fx 3.0
|
|
implementation.
|
|
.Sh BUGS
|
|
The System V
|
|
.Fn strtok ,
|
|
if handed a string containing only delimiter characters,
|
|
will not alter the next starting point, so that a call to
|
|
.Fn strtok
|
|
with a different (or empty) delimiter string
|
|
may return a
|
|
.Pf non- Dv NULL
|
|
value.
|
|
Since this implementation always alters the next starting point,
|
|
such a sequence of calls would always return
|
|
.Dv NULL .
|