memcpy

#include <stdio.h>#include <stdlib.h>#include <string.h>void* memcpy_c(void* dst, void* src, size_t count);struct{char name[40];int age;}person, person_copy;int main(void){char myname[] = "luohan";memcpy_c(person.name, myname, strlen(myname)+1);person.age= 24;memcpy_c(&person_copy, &person, sizeof(person));printf("person_copy: %s, %d\n", person_copy.name, person_copy.age);return 0;}void* memcpy_c(void* dst, void* src, size_t count){void* ret = dst;while(count--){*(char*)dst = *(char*)src;dst = (char *)dst + 1;  src = (char *)src + 1;}return ret;}