is a process of finding and reducing the number of bugs, or defects, in a computer program, thus making it behave as expected

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0
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2answers
69 views

Emacs how do I interpret this Lisp debugger report

I am trying to make up a .emacs file on my new Fedora 20 computer, and get this line when I use emacs -debug-init &. I expect it to be a trivial mistake, but I find the help on this too detailed ...
0
votes
1answer
48 views

Script in C shell skipping over last else statement?

This is a C shell script that checks the number of arguments and if the file/directory exists. When the arguments are valid, it should go to the last else statement and print "hi", but when I run this ...
0
votes
2answers
170 views

System too slow [closed]

My linux system is responding very slowly.I should wait to get the result of my command. How can i investigate to know the problem of his behavior?
2
votes
1answer
131 views

Best practices for maintaining error logs (system, device driver & application)

I have many Pandaboards with Ubuntu armhf and one PC server networked with Wi-Fi. On each embedded board I have a real-time application running constantly. I don't know how to reasonably maintain the ...
8
votes
2answers
915 views

How exactly does printk work internally?

I know printf needs help from the OS to do its job. I also know printf does not work in the Linux source code as there is no library. And so we have printk for debugging. How does printk work ...
2
votes
0answers
93 views

“Debugging” with bashdb: why do I lose command echo after stepping into a simple script?

I heard about the bash debugger ( bashdb ) after reading a comment so I thought I should try it out and see if it can help me analyze bash scripts or more generally the execution of commands. There ...
2
votes
2answers
56 views

How to tell which files have been created by an application?

I want to find out what files an application has created or modified. In the old days it was easy. cc foo.c created a.out, cc -o foo foo.c created foo, cc -c foo.x created foo.o. Now applications ...
1
vote
0answers
116 views

Why is the service unavailable the second time?

How can this happen? /volume1/homes/me $ tdtool --list /volume1/homes/me $ tdtool -e 44 Learning device: 44 - Could not connect to the Telldus Service /volume1/homes/me $ tdtool --list Error fetching ...
4
votes
1answer
72 views

Methods to diagnose why an application works for local user account but fails on a network user account?

I have setup a CentOS 6.5 machine that is attached to my company's domain. The OS is configured to allow Active Directory authentication so we do not have to have separate usernames and passwords to ...
2
votes
0answers
110 views

Is there an equivalent of addr2line on AIX system?

I'd like to debug proftpd on AIX and according to the documentation, addr2line is a usefull binary to identify what is not working. Extract of proftpd debugging documentation: The key here for ...
2
votes
1answer
576 views

How can we trace problems of crashing programs in Linux?

If an application crashes in Windows we can check the Event Viewer in the Administration tools to see what has crashed. Sometimes it has useful information others not, but it is a start. In linux if ...
1
vote
1answer
354 views

Resolving executable user stack trace addresses in ftrace

I'm trying to obtain a user stack trace in ftrace, but for some reason, only my user program cannot resolve the addresses to symbols. First, the OS I'm using is: $ uname -a Linux mypc ...
10
votes
2answers
924 views

Observing a hard-disk write in kernel space (with drivers/modules)

Apologies in advance if this post is a bit dense/messy, but I'm having a hard time formulating it better... Basically, I would like to study what happens upon a hard disk write, and I'd like to know: ...
2
votes
0answers
277 views

How should I enable the trace log for ALSA hda_unsol_event?

I have reported an ALSA kernel bug and have been asked to "enable tracepoints" and "check the response of hda_unsol_event". I was directed to the kernel docs for instruction, which say: Except ...
1
vote
1answer
453 views

Bash option to get resolved executable path?

Bash is able to trace execution script commands with the -x command line option. Each command is then output to stderr, prefixed by PS4 as stated in the man page. -x After expanding each ...
0
votes
0answers
20 views

Multiply 2 array index variables shell programming [duplicate]

How do i multiply 2 array index variables given the following foo=(1 2) bar=(0.1 0.2) foobar=$((foo[1]*price[1])) # this is wrong echo "$foobar" Current output : 0 Correct/Expected output : 0.4
1
vote
1answer
262 views

what are some of the best resources to learn advanced debugging techniques using gdb? [closed]

I know the basics of how to use gdb. But I would like to learn some advanced debugging techniques using gdb. What are the best resources - books, blogs, tutorials - that any of you use regularly. I ...
1
vote
0answers
173 views

How to trace calls to library from library?

I have an program that calls libcurl, and libcurl calls libgssapi_krb5. If I want to debug calls to libcurl, then ltrace works. But now I want to debug calls to libgssapi_krb5, then ltrace ...
2
votes
4answers
89 views

Is it possible to trace Linux source from initial bootup to desktop-GUI userland code?

I am wondering if, since Linux is 100% open-source, it is possible to follow line-by-line instructions of Linux to observe how the OS works entirely, so that one may get a better knowledge of how OSes ...
1
vote
2answers
573 views

How to “listen” to nginx writes to a file socket

I'm trying to get uwsgi and nginx to play nice. After moving to "file sockets" (hopefully I'm using the right terminology here) from TCP sockets, the only thing I get from uwsgi is a 400 with no ...
2
votes
1answer
273 views

How can I run gdb in one machine and run kgdb kernel in another machine?

I want to run two machine: debugged machine: compiled kernel with kgdb option. debugger machine: for running gdb How can I debug machine 1 from machine 2?
4
votes
2answers
2k views

Install debug flash player in Chrome?

I am trying to adapt the instructions from here, here, and here to install the debug version of the flash player on my Ubuntu 13.04 installation such that Chrome 30.0.1599.66 can use it. ...
3
votes
0answers
98 views

Understanding line numbers reported when using eval

Okay, so I'm stuck working with a shell script that needs to use eval (I know, I know, ultimate evil etc…) however I'm having difficulty debugging some of the line numbers being thrown out by errors. ...
0
votes
1answer
59 views

Getting Sublime + xDebug to work on Debian

I have been trying to get sublime and xdebug to work on debian, but have had no luck. I can't seem to find any debian specific guides. I have tried using the ubuntu based guides, but they don't work ...
1
vote
3answers
121 views

How do I know on which IDE to edit a project's source code?

EDIT: Thanks to all answerers and commenters, there's enough material to keep me busy for a while ! I recently switch to Linux and wanted to do my first development steps with the following ...
3
votes
3answers
2k views

Sound Problems with pulseaudio

The overall question that my whole problem is kind of based on is regarding sound in linux. Should I be using alsa or pulse or what? I'm using pulse at the moment and this is my problem: I was in the ...
5
votes
1answer
2k views

Kernel and QEMU : Unable to mount root fs error

I am trying to run a distro in the virtual disk image with a custom kernel,so that I can experiment and debug the kernel. I followed this to make a disk image and then install Debian to it. Now I ...
2
votes
0answers
591 views

My Debian freezes

I installed a fresh Debian 7 install, but it freezes from time to time, and when it happens (quite often indeed) only the mouse can move around but everything is blocked. All I can do is restart. I ...
1
vote
1answer
191 views

Linux, Debugger program development

We are trying to implement the debugger program which will takes either PID or Program name as input and Invoke the gdb by using PID. Below is two small programs are written, Not able to figure out ...
4
votes
4answers
7k views

How to view core files for debugging purposes in Linux?

I want to view the contents of a core file while debugging a program. How can I view the contents of a core file?
2
votes
1answer
673 views

Debugging dmesg logs

I noticed I have the following in my logs. I just am not sure as to how to go about figuring out how to fix or find out what is causing them and if they are serious. [582046.956291] Core dump to ...
6
votes
2answers
686 views

Is it possible to strace the builtin commands to Bash?

Inspired by this question, titled: When are the built-in commands loaded to memory, while attempting to answer this I tried the following command and was a bit surprised that I couldn't run it: $ ...
3
votes
1answer
118 views

detect process that executes portscans

I have to administer an ubuntu 12.04 server, where there seem to go portscans to the whole subnet. How can I find out the process that does the scans? pstree init─┬─acpid ...
12
votes
2answers
1k views

Equivalent of “truss -T” and “truss -U” on Linux?

Is there an equivalent of what the -T and -U option of the truss Solaris utility does on Linux. Those are to specify a system call (-T) or library function (-U) which when called by the traced ...
2
votes
2answers
87 views

whats a good tool to search tail -f output

I am dumping some debug info into a text file that I am using tail -f to monitor. Is there a tool that I can then pipe that tail -f data into to be able to search the text on screen using regular ...
13
votes
5answers
9k views

Can we get compiler information from an elf binary?

Is there some chance to know how a binary was built, under Linux? (and or other Unix) Compiler, version, time, flags etc... I looked at readelf and couldn't find much, but there might be other ways ...
3
votes
1answer
241 views

How to increase ftrace precision to microseconds?

I'm trying to generate FTrace files inside an Android environment, using: root@adroid:# echo 1 > /sys/kernel/debug/tracing/events/sched/sched_switch/enable root@adroid:# echo 1 > ...
3
votes
2answers
2k views

Missing separate debuginfo for - GDB

I have mentioned -g option along with -Wall in the Makefile. When I run gdb onlineSunday, I get: Missing separate debuginfo for /usr/lib64/kde4/plugins/imageformats/kimg_dds.so Try: zypper install ...
1
vote
1answer
323 views

How can I force my wifi to connect to a G-band channel?

I'm trying to debug a buggy wireless card and would like to force my Linux computer to connect using one of the g-band channels. How can I achieve this?
1
vote
1answer
627 views

Best practices for attaching debug symbols to system libraries during development?

I'm at a stage in a project where it would be really handy to have a debug version of a system package installed. On Ubuntu at least, adding the debug symbols to a library is a piece of cake. ...
5
votes
1answer
215 views

Debugging lock-up - systemd loses my logs

Ever since I have "upgraded" to systemd on Arch Linux, I keep losing logs when an unexpected lockup happens. I hit the same log-losing issue one month ago and just hit the issue again. There are also ...
4
votes
2answers
805 views

Unix/Linux C++ debugger that supports STL containers?

Currently I am using gcc-4.3.6 and Eclipse IDE for c++ development. I want to debug my project in Eclipse with gdb. I am having a hard time debugging code when it contains STL containers. Also I am ...
6
votes
2answers
1k views

Dump process core without killing the process

Is there a way to get a core dump (or something similar) for a process without actually killing the processes? I have a multithreaded python process running on an embedded system. And I want to be ...
3
votes
2answers
675 views

Shell script debugging

I was wondering if there is an IDE that would allow me to define an ssh connection to a remote host, connect, and locally debug a script running remotely (kind of like you can debug a remote Java app ...
1
vote
1answer
343 views

Killed `rm` and `cp` on nfs share

I am just testing an rsnapshot installation on my laptop which should backup to a NAS mounted via nfs on my laptop. On one test rsnapshot died with a cp -al problem (i.e. a problem with hard links) ...
4
votes
2answers
3k views

Can gdb debug suid root programs?

I wrote a program that calls setuid(0) and execve("/bin/bash",NULL,NULL). Then I did chown root:root a.out && chmod +s a.out When I execute ./a.out I get a root shell. However when I do gdb ...
1
vote
1answer
671 views

How to avoid overflowing the kernel printk ring buffer?

I'm trying to debug a linux driver and a particular piece of code is behaving very strangely. In order to see what's going on I've filled the code with printk statements so I can see exactly what the ...
2
votes
0answers
56 views

kgdb not returning control to gdb

I've compiled a kernel with kgdb support and I'm trying to debug it. I have two machines running, a debug machine (running the kgdb kernel) and the machine I'm using to debug it. They are connected ...
22
votes
4answers
2k views

Kernel Hacking Environment

I have been working in embedded OS like uCOS, ThreadX. While I have coded apps in Linux, now I’m planning to start learning Linux Kernel. I have few questions regarding the environment. Which is ...
5
votes
2answers
349 views

How to debug an inserted kernel module?

I would like to debug a loaded kernel module I don't have the source code to; I suspect it's a virus. Is there a way to feed it into GDB for analysis?