c/string/byte/strstr

@1@Finds the first occurrence of the null-terminated byte string pointed to by in the null-terminated byte string pointed to by. The terminating null characters are not compared. @2@

The behavior is undefined if either or  is not a pointer to a null-terminated byte string.

Return value
Pointer to the first character of the found substring in, or a null pointer if such substring is not found. If points to an empty string,  is returned.