.Bf -symbolic 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 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 separate context pointers are used.
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.
The following uses strtok_r to parse two strings using separate contexts:
char test, blah;
char *sep = "\\/:;=-";
char *word, *phrase, *brkt, *brkb;
for (word = strtok_r(test, sep, &brkt);
word = strtok_r(NULL, sep, &brkt))
for (phrase = strtok_r(blah, sep, &brkb);
phrase = strtok_r(NULL, sep, &brkb))
printf("So far were at %s:%s\n", word, phrase);
memchr(3), strchr(3), strcspn(3), strpbrk(3), strrchr(3), strsep(3), strspn(3), strstr(3), wcstok(3)