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STRTOK(3)		     Library Functions Manual		       STRTOK(3)

NAME
     strtok, strtok_r -- string tokens

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <string.h>

     char *
     strtok(char *str, const char *sep);

     char *
     strtok_r(char *str, const char *sep, char **last);

DESCRIPTION
     This interface is obsoleted by strsep(3).

     The strtok() function is used to isolate sequential tokens in a null-termi-
     nated  string,  str.   These tokens are separated in the string by at least
     one of the characters in sep.  The first time that strtok() is called,  str
     should  be  specified;  subsequent  calls, wishing to obtain further tokens
     from the same string, should pass a null pointer  instead.   The  separator
     string, sep, must be supplied each time, and may change between calls.

     The implementation will behave as if no library function calls strtok().

     The  strtok_r()  function	is a reentrant version of strtok().  The context
     pointer last must be provided on each call.  The  strtok_r()  function  may
     also be used to nest two parsing loops within one another, as long as sepa-
     rate context pointers are used.

RETURN VALUES
     The  strtok() and strtok_r() functions return a pointer to the beginning of
     each subsequent token in the string, after replacing the token itself  with
     a NUL character.  When no more tokens remain, a null pointer is returned.

EXAMPLES
     The following uses strtok_r() to parse two strings using separate contexts:

     char test[80], blah[80];
     char *sep = "\\/:;=-";
     char *word, *phrase, *brkt, *brkb;

     strcpy(test, "This;is.a:test:of=the/string\\tokenizer-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\n", word, phrase);
	 }
     }

SEE ALSO
     memchr(3),  strchr(3),  strcspn(3), strpbrk(3), strrchr(3), strsep(3), str-
     spn(3), strstr(3), wcstok(3)

STANDARDS
     The strtok() function conforms to ISO/IEC 9899:1990 ("ISO C90").  The  str-
     tok_r() function conforms to IEEE Std 1003.1-2001 ("POSIX.1").

AUTHORS
     Wes Peters <wes@softweyr.com>, Softweyr LLC

     Based on the FreeBSD 3.0 implementation.

BUGS
     The System V strtok(), if handed a string containing only delimiter charac-
     ters,  will  not  alter the next starting point, so that a call to strtok()
     with a different (or empty) delimiter string may return a	non-NULL  value.
     Since this implementation always alters the next starting point, such a se-
     quence of calls would always return NULL.

FreeBSD ports 15.1		January 22, 2016		       STRTOK(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=strtok&sektion=3&manpath=FreeBSD+15.1-RELEASE+and+Ports>

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