The buffer when using recv

[AxAn]

Hi.


All examples I have seen that use recv (in C wich is what I use) has had the buffer (that is filled up with recv) declared as:

char buffer[256];

I have done the following:

char *buffer=NULL;
buffer=malloc((BUFFSIZE)*sizeof(char));

and it all seem to work fine until the end of my function where I try to free the allocated memory with:

free(buffer);

Then the program buggs out on me.
Since I´m running MS VC++ I´ve done some debugging on it but haven´t found out why this is happeninig. buffer is allocated and contains info when trying to do the free().

So I wonder if it might be so that recv messes up my allocated buffer since I did get it thru malloc?

Or do anyone have another point of view?

[jim mcnamara]

This runs error free on my system using straight ansi C:

#include <stdlib.h>
#define BUFFSIZE 256
int main(int argc, char *argv[]){
   char * buffer=NULL;
   buffer=malloc(BUFFSIZE * sizeof(char));
   memset(buffer, 0x00, (BUFFSIZE * sizeof(char)) );
   free(buffer);
}

You have to be diddling with buffer somewhere, or dereferencing it:

buffer=NULL;

someplace else in your code

[AxAn]

You did not call recv.
I wonderd if that messed things up or not.

[jim mcnamara]

If you're talking about sockets (winsock), recv() does not invalidate the buffer pointer.

You have to be doing something to the pointer yourself, in your code.