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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-
       terminated 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  in-
       stead.	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 con-
       text pointer last must be provided on each call.	 The strtok_r()	 func-
       tion  may also be used to nest two parsing loops	within one another, as
       long as separate	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  it-
       self  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  con-
       texts:

       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),
       strspn(3), strstr(3), wcstok(3)

STANDARDS
       The strtok() function conforms to ISO/IEC 9899:1990 ("ISO  C90").   The
       strtok_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
       characters, 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 sequence of calls	would always return NULL.

FreeBSD	14.3		       January 22, 2016			     STRTOK(3)

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<https://man.freebsd.org/cgi/man.cgi?query=strtok&sektion=3&manpath=FreeBSD+14.3-RELEASE+and+Ports>

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