Implement strcpy and memcpy functions by yourself without library functions.

Implement strcpy and memcpy functions by yourself without library functions

1. Code Implementation

Char * strcpy (char * strdest, const char * strsrc)
{
Assert (strdest! = NULL & strsrc! = NULL );
Char * strtmpd = strdest;
While (* strtmpd ++ = * strsrc ++ )! = '0 ')
{
}
Return strdest;
}

Void * memcpy (void * pdest, const void * psrc, unsigned int size)
{
Assert (pdest! = NULL & psrc! = NULL );
Byte * ptmpd = (byte *) pdest;
Byte * ptmps = (byte *) psrc;
While (size --> 0)
{
* Ptmpd ++ = * ptmps ++;
}
Return pdest;
}

2. Differences between strcpy and memcpy

(1). strcpy can only be used for string copying, while memcpy is a memory copy that can copy any type of data.

(2) When both strings are copied, strcpy completes the string ending with '/0', while memcpy only copies the original memory, no matter what it encounters.