Hi,
Well, don't worry, I handle errors a little bit bellow ;-)
My question is that I don't understand why when
calling malloc it gives me a "segmentation fault"
while there is still a LOT of available memory....
Moreover, when I put 512 instead of 256 bytes for malloc, it seems
to work. There must be an explanation of why it
does that this segmentation fault with 256....
Thanks again for your response,
MB
William J Beksi wrote:
Mounir Bakkali wrote:
Hi everything,
Here is the issue:
I am trying to allocate some memory for my data structure
and after a msecs, I get a "segmentation fault" right after
"allocating mem"....
but if I change the size of the malloc from 256 to 512, it works just
fine.
My guess is that somehow, internal there is a segmentation fault but not
in that peace of code but in another peace of code and that I get a
segmentation
fault only when I call malloc only when I try to allocate the memory....
I have checked the memory and it looks fine (lots of mem still
available at execution time
and right before the segmentation fault);
Please, can you confirm? Do you know why is it that doing so??
Is there a way to prevent such behaviour?
You never check the return value of malloc, it's not guaranteed to give
you back the amount you requested. You also don't seem to be freeing the
memory you allocate.
This is very bad:
// the following code is called about 2500 times.
printf("allocating mem\n");
my = (char*) malloc(256);
printf("GOOD!\n");
You should do something like:
if ((my = (char *)malloc(256)) == NULL) {
/* do some error handling */
}
...
/* finished using my, free memory */
free(my);
William
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