{{keywords>wiki library source code example reference}} void *memchr(const void *str, int c, size_t n); memchr finds the firs occurrence of a character and return a pointer to it. #include /* including standard library */ //#include /* uncomment this for Windows */ #include int main( void ) { char string[] = "Find the firs occurrence of a character and count it !"; if( memchr(string,'o',strlen(string)) == NULL ) { printf( "Cant find o character\n" ); } else { printf( "found character o at position %li\n", (char *)memchr(string,'o', strlen(string))-string+1 ); } return 0; } output: user@host:~$ ./memchr found character o at position 15