模拟实现strncpy

#include <stdio.h>
#include <windows.h>
#include <string.h>
#include <assert.h>


#pragma warning( disable : 4996) 


char * My_strncpy(char * dest, const char *src, size_t n)
{
assert(dest);
assert(src);


char *ret = dest;
while (n--)
{
*dest++ = *src++;
}
return ret;
}


int main()
{
char str1[20] = "123456789";
char str2[20] = "abcde";





printf("调用My_strncpy之前: str1: %s \n", str1_1);
My_strncpy(str1, str2, 5); //调用My_strncpy
printf("调用My_strncpy之后: str1: %s \n", str1);


system("pause");
return 0;
}