03-20-2019
Don't be embarassed! C is very different from most languages. It's a high-level language which writes pure assembly, with all the safety you get from pure assembly...
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1. Programming
sometimes for this code i get a segmentation fault for codes llike this
:
int main{
int * a= 0;
int b;
a = (int*)malloc(sizeof(int));
///some code using these variable but no freeing of a
if(a){
free(a);
a = 0;
}
return... (3 Replies)
Discussion started by: wojtyla
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2. AIX
Hi ,
During execution a backup binary i get following error
"Program error 11 (Segmentation fault), saving core file in '/usr/datatools"
Riyaz (2 Replies)
Discussion started by: rshaikh
2 Replies
3. Linux
Hi,
on a linux Red HAT(with Oracle DB 9.2.0.7) I have following error :
RMAN> delete obsolete;
RMAN retention policy will be applied to the command
RMAN retention policy is set to redundancy 2
using channel ORA_DISK_1
Segmentation fault
What does it mean ? And the solution ?
Many thanks. (0 Replies)
Discussion started by: big123456
0 Replies
4. Programming
If I do this.
Assume
struct life
{
char *nolife;
}
struct life **life;
// malloc initialization & everything
if(life->nolife == 0)
Would I get error at life->nolife if it is equal to 0.
wrong accession? (3 Replies)
Discussion started by: joey
3 Replies
5. Programming
I'm getting a segmentation fault. I'm new to Linux programming. Thanks so much for all of your input.:eek:
#include </usr/include/mysql++/mysql++.h>
#include <stdio.h>
#include <iostream>
#include <sstream>
#include <string.h>
using namespace std;
int outputToImport(const char*... (1 Reply)
Discussion started by: sepoto
1 Replies
6. Programming
i have this code
int already_there(char *client_names, char *username) {
int i;
for(i = 0; i<NUM; i++) {
printf("HERE\n");
if (strcmp(client_names, username)==0) return(1);
}
return(0);
}
and i get a segmentation fault, whats wrong here? (7 Replies)
Discussion started by: omega666
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7. UNIX for Advanced & Expert Users
What does this mean and why is this happening?
$ ps -ef | grep ocular
Segmentation fault (core dumped)
$ ps -ef | grep ocular
Segmentation fault (core dumped)
$ ps aux | grep ocular
Segmentation fault (core dumped)
$ ps
Segmentation fault (core dumped)
$ pkill okular
$ ps... (1 Reply)
Discussion started by: cokedude
1 Replies
8. Programming
I use a binary name (ie polo) it gets some parameter , so for debugging normally i do this :
i wrote script for watchdog my app (polo) and check every second if it's not running then start it , the problem is , if my app , remain in state of segmentation fault for a while (ie 15 ... (6 Replies)
Discussion started by: pooyair
6 Replies
9. Homework & Coursework Questions
this is a network programming code to run a rock paper scissors in a client and server.
I completed it and it was working without any error. After I added the findWinner function to the server code it starts giving me segmentation fault.
-the segmentation fault is fixed
Current problem -Also... (3 Replies)
Discussion started by: femchi
3 Replies
10. Solaris
Hi Guys,
I just installed and booted a zone called testzone. When I logged in remotely and tried changing to root user I get this error:
"Segmentation fault"
Can someone please help me resolve this?
Thanks alot (2 Replies)
Discussion started by: cjashu
2 Replies
LEARN ABOUT REDHAT
njamdpm
NJAMDPM(1) General Commands Manual NJAMDPM(1)
NAME
njamdpm - Not Just Another Malloc Debugger Post-Mortem
SYNOPSIS
njamdpm [OPTIONS] <HEAP FILE>
DESCRIPTION
njamdpm is a companion utility that allows you to examine the persistent heap saved by libnjamd(3) You can do things like query for certain
addresses, show memory leaks, and show all past allocated memory. As of NJAMD 0.6.0, gdb(1) is required to make sense of the return
addresses.
USAGE
Options
HEAP FILE
The heap file will be in the current directory with a name of the form njamd-<pid>-heap, but only if NJAMD_PERSISTANT_HEAP was in
the environment at the time of program execution
-a address
Search through the heap file for a chunk of memory that contains address. This can be VERY helpful when using gdb. Simply find the
address that you accessed to cause the segmentation fault, use njamdpm to look it up in the heap, and viola! You have all sorts of
info about the chunk: When it was allocated, when it was freed, how big is is, etc.
-d depth
When displaying return address info, only display depth return addresses. The max is specified in ./include/lib/njamd.h in the
define TRACE_DEPTH (default is 3).
-t Trim the heap file down to only the used portion. This is useful if for some reason the program somehow exits without trimming its
own heap file down first. Note that when the heap file appears huge it's not actually taking up disk space.
-s Dump basic status info about peak memory usage, NJAMD overhead, etc. Useful for determining if you should buy more ram, or write me
an angry email :)
-l Dump memory leaks in the heap. Also shows you info about where the memory was leaked, along with a total. Do note that this total
and the subtotals are aligned bytes. They are aligned to the alignment of your architecture, or as specified by the value the
NJAMD_ALIGN environment variable had when the heap was created.
-f Dump freed memory in the heap. This option is only available if LIBNJAMD ran without NJAMD_CHK_FREE=none set.
Using gdb with njamdpm
When a segmentation fault happens, it's because, of course, you accessed an invalid address. So all you need to do is get gdb to give you
the address you accessed, and then feed it to njamdpm. Ie if the segfault occurs on a line that does buf[i] = 2, issue print &buf[i] to
gdb. Note that libnjamd(3) now has a function __nj_ptr_info that can be called from gdb that performs all this without njamdpm.
To get gdb to translate these return addresses into something meaningful, issue
info line *0xaddress
to obtain the line number of the allocation request, or
list *0xaddress
to see the adjacent code as well.
NOTES
Eventually I hope to add symbol translation right into njamdpm.
AUTHORS
Mike Perry <mikepery@fscked.org>
SEE ALSO
http://freshmeat.net/appindex/development/debugging.html
njamd(3), efence(3), malloc(3), mmap(2), mprotect(2)
NJAMD - 5 Oct 2000 NJAMDPM(1)