why debug step by step, it s ok

Hi all,


I have one simple program:
#define __EXTENSIONS__
#include <stdio.h>
#include <string.h>


int main() {
char *buf="5/90/45";
char *token;
char *lasts;


printf("tokenizing \"%s\" with strtok():\n", buf);
if ((token = strtok(buf, "/")) != NULL) {
printf("token = \"%s\"\n", token);
while ((token = strtok(NULL, "/")) != NULL) {
printf("token = \"%s\"\n", token);
}
}
}

the program has abused the strok, i know it,

******but why when i `gdb prog_name` and execute step by step , it 's
ok?


thanks

baumann@pan

.