memmove memcpy

Linux 中两函数象征性实现

void  * memcpy ( void  * dest, const   void  *src, size_t  count)
{
     char  *tmp = ( char  *) dest, *s = ( char  *) src;
     while  (count--)
        *tmp++ = *s++;
     return  dest;
}

void  *memmove ( void  * dest, const   void  *src, size_t  count)
{
     if  (dest < src) { 
        __inline_memcpy(dest,src,count);
    }  else  {
         char  *p = ( char  *) dest + count;
         char  *s = ( char  *) src + count;
         while  (count--)
            *--p = *--s;
    }
     return  dest;
}