extern int strcasecmp(const char *s1, const char *s2);
extern int strncasecmp(const char *s1, const char *s2, size_t n);
+extern char *strnstr(char *s, const char *find, size_t slen);
extern char *strchr(const char *s, int c);
extern char *STRDUP(const char *, int);
extern int strprefix(const char *s1, const char *s2);