Key Points of implementing memcpy Functions

Void * memcpy (void * dest, constvoid * src, size_tcount) // 1. The source string must have the const Modifier
{
Char * pDest = (char *) (dest); // 2. Assign the original pointer to the new variable
Const char * pSrc = (constchar *) (src );

// 3. The destination address overlaps with the source address and starts copying from the end of the source address.
If (pDest> pSrc & pDest <pSrc + count)

{

// Point the pointer to the end

PDest = pDest + count-1;
PSrc = pSrc + count-1;
While (count --){
* PDest -- = * pSrc --;
}
}
// 4. The destination address and source address do not overlap and are copied from the beginning of the source address.
Else
{
While (count --){
* PDest ++ = * pSrc ++;
}
}

Return pDest; // 5. return, which can be nested
}

Author: "The column of the catalogue with big smoke"