1 #include <string.h> 2 3 char* __strchrnul(const char*, int); 4 strchr(const char * s,int c)5 char* strchr(const char* s, int c) { 6 char* r = __strchrnul(s, c); 7 return *(unsigned char*)r == (unsigned char)c ? r : 0; 8 } 9