strstr()

  #include <string.h> 

  

  char *strstr(const char *p, const char *q);

  

strstr() looks for substring q appearing in string p.

A pointer to the beginning of the first occurrence of string q in p, or NULL, if q does not appear in p.

strchr(),

strcspn(),

strpbrk(),

strrchr(), and

strspn()