Convert hex string to byte array

hex2bin.c

#include <stdio.h>
#include <stdlib.h>

int main(int argc, char** argv) {
    const char raw_payload[] = "11ff0e3b0001ff00ff0000000000";
    const char *pos = raw_payload;
    unsigned char payload[14];
    size_t cnt = 0;

    for (; cnt < sizeof(payload) / sizeof(payload[0]); ++cnt) {
        char buff[5] = {'0', 'x', pos[0], pos[1], 0};
        payload[cnt] = strtol(buff, NULL, 0);
        pos += 2 * sizeof(char);
    }

    printf("0x");
    for (cnt = 0; cnt < sizeof(payload) / sizeof(payload[0]); ++cnt) {
        printf("%02x", payload[cnt]);
    }
    printf("\n");

    return 0;
}