strtok

NAME

<span class="Nm" id="strtok">strtok</span>, <span class="Nm" id="strtok_r">strtok_r</span>

INTERFACE

#include <string.h> char strtok ( char *str, const char *sep ) char strtok_r ( char *str, const char *sep, char **last )

DESCRIPTION

<span class=""> This interface is obsoleted by reference:strsep (3) . </span> &#92;n &#92;n The strtok function is used to isolate sequential tokens in a null-terminated string, &#92;c str. These tokens are separated in the string by at least one of the characters in &#92;c sep. The first time that strtok is called, &#92;c str should be specified; subsequent calls, wishing to obtain further tokens from the same string, should pass a null pointer instead. The separator string, &#92;c sep, must be supplied each time, and may change between calls. &#92;n &#92;n The implementation will behave as if no library function calls strtok . &#92;n &#92;n The strtok_r function is a reentrant version of strtok . The context pointer &#92;c 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 separate context pointers are used. &#92;n &#92;n 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 <span class="Dv">NUL</span> 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) , reference:strsep (3) , strspn (3) , strstr (3) , reference:wcstok (3)

STANDARDS

The strtok function conforms to

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- <span class="Dv">NULL</span> value. Since this implementation always alters the next starting point, such a sequence of calls would always return <span class="Dv">NULL</span>.

AUTHORS

<span class="An">Wes</span> <span class="An">Peters</span>, &#92;n Softweyr LLC: <<span class="Aq">wes@softweyr.com</span>> &#92;n &#92;n Based on the FreeBSD 3.0 implementation.