Comments on: I’m a Zero

By: Man

Man — Tue, 21 Dec 2010 04:09:48 +0000

memset, folks. oneliner.

By: Nix

Nix — Tue, 29 Sep 2009 20:05:23 +0000

Why wouldn’t you just do this –

void clearMemory(void *pStartByte, int numBytes)
{
while ( numBytes– ) *((char*)pStartBytes) = 0;
}

By: Rodneyk

Rodneyk — Mon, 04 Feb 2008 19:26:57 +0000

Depending on the objective the first solution listed above can be improved. The first solution does a memory access for every byte of memory being initializes. However most modern CPUs (80286 and higher for Intel) can access memory at 32 bits or more. So why waste cycles hitting memory by bytes…

void ClearMemory(void* pStartMem, int numBytes)
{
unsigned long *plMem = (unsigned long *)pStartMem;
unsigned char *pcMem = (unsigned char *)pStartMem;

if (pStartMem == NULL)
return;
while(numBytes > sizeof(unsigned long))
{
*plMem++ = 0;
numBytes -= sizeof(unsigned long);
}
pcMem = (unsigned char *)plMem;
while(numBytes–)
{
*pcMem++ = 0;
}
}

By: kiklop

kiklop — Sat, 30 Dec 2006 17:59:57 +0000

void clearMemory(void *pStartByte, int numBytes) {
if (pStartByte == NULL) {
return;
}
char* buffer = (char*)pStartByte;
while (numBytes–) {
*buffer++ = ”;
}
}