Programming :: C - Segfault During Malloc. How To Use The Pointers
Mar 23, 2010So the place where I'm having a problem is here:
Code:
typedef struct {
void **Mem_Chunk;
[code]...
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Programming :: C - Malloc Causing Segfault?
Mar 20, 2010Code:
#include <stdio.h>
#include <stdlib.h>
[code]...
Programming :: C - How To Malloc For A Structure
Mar 7, 2010How do you malloc a struct in C? I have a structure of the form:
Code:
typedef struct child_req_to_parent
{
[code]...
Programming :: Arrays In The C Programming Language Are Pointers To The First Element Of The Array?
Mar 27, 2010I wonder why arrays in the C programming language are pointers to the first element of the array, not the first element of the array itself?
View 14 Replies View RelatedProgramming :: C - Malloc For A Void Pointer?
Mar 20, 2010So far I have this:
Code:
int mm_init (mm_t *MM, int hm, int sz) {
int i;
[code]...
Programming :: Why Malloc() Blocks/sleeps
Jun 2, 2010I have encountered this scenario wherein malloc does not return.
Code:
char * tmp;
rs = 100 to 40000 bytes
[code]...
Programming :: Malloc Fails To Allocate Memory
May 7, 2011I am developing a code where I need to store the planes of an object in a tree & also i need to store it in a list for further processing ... when I try to allocate using malloc the memory allocation when i checked this in internet , I came to know that it may because the memory that I am trying to allocate may be more than the size_t variable.
View 9 Replies View RelatedProgramming :: Hooking Calls To New/malloc Delete/free?
Jan 11, 2010Is there a way to hook calls to new/malloc, delete/free in C++? I tried the following methods: LD_PRELOAD -> fails for malloc, because dlsym seems to depend on malloc -Wl,--wrap,malloc -> doesn't work for 'new' gcc hooks -> doesn't work always, e.g. for uclibc there are no hooks Are there any other methods I could try?
View 2 Replies View RelatedProgramming :: C With Gcc: Are All Variables Defined Like Pointers
Sep 13, 2010i'm practicing in very basic c programs using the gcc compiler.I found that when i create two variables let's say
Code:
int a,b and Code: a=15;
b=3;
a=b;
b--;
then a equals 2.I thought that this isn't normal in C isn't it?I haven't had the time to read the gcc documentation yet...so i think it has something to do with my compiler's default settings.I use the
Code: gcc filename.c -o filename command to compile
Are all variables defined like pointers?
Programming :: Difference Between Two Arithmetic Pointers
Jun 1, 2010What is the difference between *ptr++ and (*ptr)++. In my opinion the terminology is all over the place so if you could give an example it would be better.
View 8 Replies View RelatedProgramming :: Function Pointers To Class Members Cpp
May 23, 2010i'm a bit stuck playing with the following class setup for glut. The actual issue is with the function pointers.Basically the following code is the opengl redbook cube example slightly modified.
View 2 Replies View RelatedProgramming :: Function Pointers With Variable Arguments
Jul 14, 2011I need to call functions that match an input string (if input str = "func1", call func1), so I have this:
Code:
#include <stdio.h>
#include <string.h>
void function_a(void) { printf("Function A
"); }
[Code].....
In the above example, the functions take no input arguments. Can they take a different number of arguments, for example, function_a(int), function_c(int, int), function_e(int, char, int)? How can I do that?
Programming :: Passing Local Variable Pointers In ASM
Apr 12, 2010I want to know is there some more efficient way of passing a pointer to a local variable as a parameter to a function in x86 asm? Right now I have to move the base pointer to a temp register, subtract from the register and pass that, like this (assuming a local var at esp-4):
Code:
mov eax, ebp
sub eax, 4
push eax
Is there a better way?
Programming :: Perl - Pointers To Arrays From Hashes?
Feb 18, 2010I'm trying to figure out how to code for this specific type of instance - I want to use a hash and have the key be a reference to an array, and not use the key in the standard way of it being a scalar. Basically, I have a large output that I need to process line by line, and rather have access to it as an array than a big block in a scalar. For the big block hash as a scalar I would do -
Code:
foreach $CONTROLLER (<CONTROLLER_LIST>) {
$ALL_DISKS{$CONTROLLER} = `ssh -n <commands>`;
}
Now I know I could take the scalar and split it to another array after the fact like -
Code:
@TEMP_HOLD = split (/s+/,$ALL_DISKS{$CONTROLLER});
How would I code it that I would have access to the key information as an array and not a scalar? I know it needs to be a pointer and we're going to have -> in there somewhere, but not sure how to approach it. Some of the documentaiton I've been reading about referencing I've found a little confusing so far, and trying to figure out how to use them in context of what I'm working on.
Programming :: Is Spacing As Used Non-factor When Declaring Pointers?
Jul 3, 2010I've seen all three uses:
type * pointer
type *pointer
type* pointer
Are these 3 forms essentially the same, i.e., is the spacing as used here a non-factor when declaring pointers?
Programming :: How To Pull Node Pointers Out Of The Model
Mar 25, 2010I am trying to find a way to pull Node Pointers out of the model, for use in other areas of the program. The solution is probably simple but I haven't had any luck finding it.
Model for a QTreeView:
Code:
class testModel : public QAbstractItemModel
{
public:
testModel();
~testModel();
[code]....
Programming :: Two Pointers, That Have The Same Address Point To Different Values?
Feb 17, 2011I have the most strange problem ever in programming. I fork a process into a parent and a child. In every forked process i declare a pointer, malloc and define a different value for every pointer.When i printf the value and the address guess what? They both have the SAME ADDRESS but DIFFERENT values, as assigned..Here's the portion of my code:
pid = fork ();
switch (pid)
{
[code]....
Programming :: Sizeof Struct With Function Pointers As A Member?
Jul 2, 2010I following structure
typedef struct
{
[code]...
Programming :: Double Pointers / Matrix GCC (fill It One Column With Zeros And The Other With Ones)
May 26, 2011I have a 10x2 matrix, I create said matrix and fill it one column with zeros and the other with ones, now when I print the matrix I get this:
column 1:
0,0,0,0,0,0,0,0,1,1
column 2:
1,1,1,1,1,1,1,1,1,1
The first two rows of the second column are being replaced into the last two rows of the first column, now I even checked in visual studio and it works fine there. A friend tried my code and he gets it even worse:
column 1:
0,0,0,0,1,1,1,1,1,1
column 2:
1,1,1,1,1,1,1,1,1,1
As far as I've seen it must be a problem with GCC, unfortunately I need to have this up and running in GCC no matter what.
[Code].....
Programming :: Segfault In Program Using Pthreads
Mar 16, 2010I am trying to write a peer to peer application in C++ using pthreads library. There are few types of nodes that run in the program. The 'beacon' nodes form the core of the network. The ordinary nodes 'join' the network by sending join requests to the beacon node. So, my program runs till the join requests and responses are received. When I try to 'connect' using connect function from the socket library, I get a segfault. I am not sure if the segfault occurs for the connect function, because sometimes the program just runs to completion. It could be an issue related to threads or memory allocation.
When I run gdb, it shows me the following:
Code:
(gdb) run b2-n00.ini
Starting program: sv_node b2-n00.ini
servant:12600> [New LWP 1]
[New LWP 2]
[New LWP 3]
[New LWP 4]
[New LWP 5]
[New LWP 6]
Before Exiting[LWP 1 exited]
procfs: fetch_registers, get_gregs line 3768, /proc/23952/lwp/1: No such file or directory.
Programming :: Fortran - Array-valued Function Leads To Segfault?
Jun 8, 2010I'm trying to implement a solver for a system of differential equations in Fortran. The solver contains a number of functions which are supposed take real values, 1D arrays of real values or both as arguments and return arrays of real numbers, all of which cause the program to segfault. Example:
Code:
function y_exakt(t)
implicit none
real::t, pi
[code]....
(the last number in the array seems to change randomly). Then the program crashes either when f(t,y) is called or when dy is returned (after removing the call to f). What could cause these (memory?) problems and/or what could I do to identify the problem? Increasing the maximum stack size with ulimit or compiling the program with -fno-automatic has had no effect. I'm using gfortran (gcc 4.4.3) on a 64-bit Ubuntu Lucid machine. The complete program can be found at [URL].
Programming :: Memory Leaks - Glibc Detected - ./SuffixTree: Malloc() - Memory Corruption - 0x00
Mar 21, 2011I am new to C and linux. My code below does arbitary writes but I cant figure out where or how it does it.
I am calling the insertNode() function with seq = 'MISSISSPPI$' and alphabets = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ$'
Code:
Weird behaviour I should mention is that when I check for NULL pointer in node->child[index], the unassigned values are not null anymore, they point to arbitary memory.
General :: In Linux Malloc() Initializes To Zero?
Nov 10, 2010#include<stdio.h>
#include<stdlib.h>
int main()
[code]...
Fedora :: Checking For GNU Libc Compatible Malloc... No \ Fix It?
Jul 13, 2010I'm trying to compile ink but with no luck. Here are the terminal output,
Code:
[trumpet@Trumpet-PC ink-0.5.1]$ ./configure
checking for a BSD-compatible install... /usr/bin/install -c
[code]...
OpenSUSE :: Getting A Weird Compilation Error With Malloc.h?
Aug 3, 2010I am getting a weird compilation error with malloc.h/usr/include/malloc.h:86: error: expected ')' before '__size'This is what the code looks like inside malloc.hextern void *(*__morecore) __MALLOC_PMT ((ptrdiff_t __size))When I did some googling, it was stating that ptrdiff_t was not defined; but, it is.#define __malloc_ptrdiff_t ptrdiff_t
View 4 Replies View RelatedServer :: Malloc-64 Memory Leak/trashing?
Mar 2, 2011I'm afraid I have a huge issue with my newest Fedora 14 server. I recently migrated to Fedora 14 from Centos 5, which was very stable, but had ancient packages and libraries and my users were revolting...The machine is a HP ProLiant 360 G7, with 12G RAM and 6 SAS drives in RAID 5.After I migrated to Fedora 14, I noticed that for some reason, during the course of about 24 hours, all usable RAM "disappears" and applications are forced down to swap space. Needless to say I didn't have this issue on CentOS.
The server does heavy IO as per it's function (it's a heavily loaded file processing server and user simulation computing station among other things, which causes lots of random IO), so I thought it may be the cache, but then I realized it cannot be - because obviously Linux will use onyl "unused" RAM for caching and frees it up as soon as an app need it. Then, I thought to check the "slabtop" to see what's going on in Kernel memory. Unfortunately I don't have the screenshot from the time just before the latest crash, but there's a certain value displayed by slabtop, which slowly, byte-from-byte creeps over all available RAM, eventually forcing applications down to the swap. This is malloc-64, and as you can see from the bellow copy-paste, it's building up again even now...
Code:
Active / Total Objects (% used) : 9118075 / 9153600 (99.6%)
Active / Total Slabs (% used) : 152157 / 152157 (100.0%)
[code]...
Ubuntu Installation :: Checking For GNU Libc Compatible Malloc?
Feb 25, 2010I have been trying to fix this problem for 3 days, any ideas before I jump through the window (not the bill gates one)?I am using ubuntu 9.10 and running a ./configure.
View 3 Replies View RelatedServer :: User-specified Malloc Function Returned NULL?
Dec 23, 2010Our Fedora-ds was down for some reason,And I got these logs:
[23/Dec/2010:18:59:32 +0200] - libdb: User-specified malloc function returned NULL
[23/Dec/2010:18:59:32 +0200] - id2entry error 12
[23/Dec/2010:18:59:32 +0200] - id2entry get error 12
[code]...
Software :: Glib Detected Malloc Memory Corruption?
Jul 21, 2011When I am trying to run my application on RHEL 6 (Kernel 2.6*), I am getting the following error.*** glib detected *** ./corenms:malloc(); memory corruption : 0x086691d0 ***
View 4 Replies View RelatedGeneral :: Clearing Of Memory Allocated By Using Malloc/kmalloc/vmalloc
Aug 8, 2011Let's analyse this While registering a Char deriver to kernel think that we had allocated memory using any of malloc/kmalloc/vmalloc.
If we forgot to Free that allocated memory while unregistering, will that memory be allocated aside or kernel clears it...?