strstr() — Locate substring

Standards

Standards / Extensions	C or C++	Dependencies
ISO C XPG4 XPG4.2 C99 Single UNIX Specification, Version 3	both

Format

#include <string.h>

char *strstr(const char *string1, const char *string2);

General description

Finds the first occurrence of the string pointed to by string2 (excluding the NULL character) in the string pointed to by string1.

Returned value

If successful, strstr() returns a pointer to the beginning of the first occurrence of string2 in string1.

If string2 does not appear in string1, strstr() returns NULL.

If string2 points to a string with zero length, strstr() returns string1.

Example

CELEBS51

⁄* CELEBS51                                      

   This example locates the string haystack in the string "needle in a          
   haystack".                                                                   

 *⁄                                                                             
#include <stdio.h>                                                              
#include <string.h>                                                             
                                                                                
int main(void)                                                                  
{                                                                               
   char *string1 = "needle in a haystack";                                      
   char *string2 = "haystack";                                                  
   char *result;                                                                
                                                                                
  result = strstr(string1,string2);                                             
     ⁄* Result = a pointer to "haystack" *⁄                                     
  printf("%s\n", result);                                                       
}

Output

haystack