Hi All,
I have written a C++ program, it can be compiled (in UNIX) but when I
run it, I usually gives the following errors:
free(): invalid pointer 0x51d4a0!
free(): invalid pointer 0x51d460!
free(): invalid pointer 0x51d760!
free(): invalid pointer 0x51d7e0!
..
..
..
Can anyone help me to know what is the reason for this problem?
Thanks,
4  4343 
c language wrote: Hi All,
I have written a C++ program,
Then you should go down the hall to the C++ group.
it can be compiled (in UNIX) but when I
run it, I usually gives the following errors:
free(): invalid pointer 0x51d4a0!
free(): invalid pointer 0x51d460!
free(): invalid pointer 0x51d760!
free(): invalid pointer 0x51d7e0!
..
..
..
Can anyone help me to know what is the reason for this problem?
Passing an invalid pointer to free? When you post on the C++ group,
include the code.
--
Ian Collins.
c language wrote: Hi All,
I have written a C++ program, it can be compiled (in UNIX) but when I
run it, I usually gives the following errors:
free(): invalid pointer 0x51d4a0!
free(): invalid pointer 0x51d460!
free(): invalid pointer 0x51d760!
free(): invalid pointer 0x51d7e0!
Can anyone help me to know what is the reason for this problem?
Why don't you try posting your question, along with a small, complete,
compilable example that demonstrates your issue, to comp.lang.c++. It
is very difficult to know exactly what the problem is without seeing
your code although, and I am going out on a limb here, you may be
trying to free an invalid pointer (i.e. a pointer that was not returned
to you by malloc and friends).
Robert Gamble
make sure the memory your pointer point to is allocated by fuction
"malloc"!
seni.yin schrieb: make sure the memory your pointer point to is allocated by fuction
"malloc"!
What are you responding to? Please quote sufficient context.
The above may be right or wrong, depending on the context.
Cheers
Michael
--
E-Mail: Mine is an /at/ gmx /dot/ de address. This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
by: Ramprasad A Padmanabhan |
last post by:
Hello all,
If I assign one pointer to another , I had assumed I can call them
interchangably.
I can explain by the example below. I am doing a malloc to char* a which
is the same as char* b. But when I free(b) the memory allocated to a
does not get freed
Can someone explain this.
|
by: kj |
last post by:
How can one test if a pointer has been "freed" (i.e. with free())?
My naive assumption was that such a pointer would equal NULL, but
not so.
Thanks,
kj
--
NOTE: In my address everything before the first period is backwards;
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Hi,
If I call free() with a uninitialised pointer, will the program
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Incidentally, is there a way in Standard C to determine
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How does free() , delete() works?
If we allocate memory using the following statement
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How does it know about how many bytes/bits to be deleted?(same is the
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by: Raman |
last post by:
Hi All,
Here is a small Code,
int main(void)
{
char *p=(char *) malloc(100);
strcpy(p,"Test1234567890");
p=p+10;
free(p);
|
by: dbansal |
last post by:
Hi group,
I have a question to ask you all. I have allocated some chunk of
memory using ptr=(int*)malloc(). now I am trying to free that memory
using free((void*)ptr). My question is does free() make ptr NULL? If
not how do we know whether ptr memory has been freed already and we
should not try to free the same memory twice. Man pages does not tell
anything about this behavoiur.
Thanks,
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