Strtok to separate all whitespace

Question

I'm trying to split a string at spaces and tabs.

char * token = strtok(input, " \t");

works only for spaces. What am I doing wrong?

Answer 1

Here is an example that illustrates that strtok() will work on tabs or spaces. The key is to pass in NULL on the all but the first call to strtok().

#include <stdio.h>
#include <string.h>
int main(int argc, char *argv[])
{
    char buffer[1024];
    int rv = sprintf(buffer, "a string\ttokenize.");
    char *token = strtok(buffer, " \t");
    int i = 0;
    printf("cnt  token\n");
    printf("==========\n");
    while (token) {
        printf("%2d %s\n", i++, token);
        token = strtok(NULL, " \t");
    }
    return 0;
}

output from above program is as follows below.

cnt  token
==========
 0 a
 1 string
 2 tokenize.