C/string.h/memchr
memchr: searches *buffer for "ch" in the first count characters
//Declaration: void *memchr(const void *buffer, int ch, size_t count);
//Return: returns a pointer to the first occurrence of ch or a null pointer if not found.
#include <stdio.h>
#include <string.h>
int main(void)
{
char *p;
p = memchr("this is a test", " ", 14);
printf(p);
return 0;
}