Synopsis
#include <string.h>
char *strstr(const char *s1, const char *s2);
Description
strstr locates the first occurrence in the string pointed to by s1
of the sequence of characters (excluding the terminating null character) in
the string pointed to by s2.
strstr returns a pointer to the located string, or a null pointer if
the string is not found. If s2 points to a string with zero length, strstr
returns s1.
Portability
strstr conforms to ISO/IEC 9899:1990 (C90) and ISO/IEC 9899:1999 (C99).