Re: Convert Int Value To Pointer

On Fri, 14 Jul 2006 19:37:20 GMT, Frederick Gotham
<fgothamNO@xxxxxxxx> wrote in comp.lang.c:

ReaperUnreal posted:

I've got a strange problem here. I need to take a value that I have
written down on a sticky-note here, and find what's at that address in
current memory. I've tried the following:

void *value = 0x00323c68;

but I get a typecasting error. If I do the following:

void *value = static_cast<void *>(0x00323c68);

will that get me what I desire?


How about something like the following?

#include <stddef.h>
#include <limits.h>
#include <stdio.h>

void PrintBits(void const * const mem, size_t amount_bytes)
{
char static str[CHAR_BIT + 1]; /* Auto null teminator */

unsigned char const *p = (unsigned char const *)mem;

do
{
unsigned char const byte_val = *p++;

char *pos = str;

unsigned char i = 1U << CHAR_BIT - 1;

do *pos++ = byte_val & i ? '1' : '0';
while(i >>= 1U);

Do you realize that there is absolutely no gain to adding the 'U'
suffix here?


printf("%s",str);

} while (--amount_bytes);
}

int main(void)
{
void * const p = (void*)0x00323c68;

PrintBits( p, 1 );
}

Do you actually this makes the behavior any less undefined? Do you do
realize that without a terminating '\n', there is no guarantee that
any output will appear?

--
Jack Klein
Home: http://JK-Technology.Com
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