1#define _GNU_SOURCE
2#include <string.h>
3
4char* strsep(char** str, const char* sep) {
5    char *s = *str, *end;
6    if (!s)
7        return NULL;
8    end = s + strcspn(s, sep);
9    if (*end)
10        *end++ = 0;
11    else
12        end = 0;
13    *str = end;
14    return s;
15}
16