Debugging is a methodical process of finding and reducing the number of bugs, or defects, in a computer program
Questions tagged [debugging]
247 questions
185
votes
8 answers
I have a hardware detection problem, what logs do I need to look into?
I am trying to ask a question about getting my hardware to work but I don't know what information to add to my question to get help, what do I need to do?
Related if you don't have access to a GUI:
How do I get information from the logs on my…
Jorge Castro
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116
votes
9 answers
There's an issue with an Alpha/Beta Release of Ubuntu, what should I do?
I've been running Alpha releases of Ubuntu for some time now. I keep running into issues - how can I get these resolved? What should I do when I encounter these problems? And where can I find other Ubuntu+1 users to ask questions?
Marco Ceppi
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103
votes
8 answers
Nginx failing to reload - how to track down why?
Hi I've had my Nginx server running great on Ubuntu server 12.04 for a while.
I've been gradually bolting on various bits, and got as far as optimising load times on my wordpress page.
After making a few changes to my hosts file I decided to:
sudo…
Huw
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74
votes
2 answers
after upgrade gdb won't attach to process
I just recently upgraded from 10.04 to 11.04 and gdb won't allow me to attach to processes anymore I get the error
Attaching to process 10144 Could not
attach to process. If your uid
matches the uid of the target process,
check the setting…
Andrew Redd
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68
votes
2 answers
How do I debug Upstart scripts?
For some reason I'm getting an error during apport upgrades, the cause of which is
% sudo service apport start
start: Job failed to start
Under sysvinit, I could debug this kind of problem by running eg
sudo sh -x /etc/init.d/whatever start
but…
poolie
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38
votes
7 answers
How to debug bash script?
Is there any way to debug bash script without using echo and logging?
I'm talking about using breakpoints and stuff like that.
UAdapter
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33
votes
3 answers
Where do I find core dump files, and how do I view and analyze the backtrace (stack trace) in one?
When I run my C program on Ubuntu 20.04, I get this run-time error:
Segmentation fault (core dumped)
I really need to find and view the core file, but I can't find it anywhere. Where is it, and how do I view the backtrace in it?
Gabriel Staples
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29
votes
2 answers
Why won't strace/gdb attach to a process even though I'm root?
I logged in as root but strace gives me this:
root@kyznecov-System:/home/kyznecov# ps -e | grep 111
3807 pts/2 00:00:00 111
3810 pts/2 00:00:00 111
root@kyznecov-System:/home/kyznecov# strace -p 3810
attach: ptrace(PTRACE_ATTACH, ...):…
andreykyz
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26
votes
4 answers
Can one pick up a running application from terminal?
Sometime I need to run an application from terminal for debugging. If I am sure the bug will occur short after launching the application, I can run this application from the Terminal.
However, bugs occur unexpectedly, and then only I need to monitor…
neydroydrec
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22
votes
2 answers
How can I find out what ibus-daemon and ibus-ui-gtk3 are doing?
Occasionally my desktop slows down a lot. The mouse pointer moves slowly or not at all, my fan starts whirring, and the end is generally nigh. If I'm very patient normality usually restores itself, but this happens daily.
Recently when it happened I…
lofidevops
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16
votes
1 answer
Why do xrandr errors "BadMatch", "BadName", "Gamma Failed" happen?
I have not found a single solution to such errors, despite the rather large number of users out there who have them.
So I want to try to find a solution myself. However, I have no idea why they occur...
Is there anyone who knows why? You don't have…
TellMeWhy
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15
votes
1 answer
How to debug an unmet dependencies problem?
Note about possible duplicate:
AFAIK, This is not a duplicate of How do I resolve unmet dependencies after adding a PPA? otherwise please prove it by solving the test problem I mention below using any answer from there.
Background:
I faced this…
user.dz
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14
votes
2 answers
How to load a module in initrd?
I want to explicitly load a module (say, netconsole) during the initrd stage, similarly to /etc/modules in the main system startup procedure.
First, I checked that the initrd in my system already contains the wanted module (see Appendix).
I have…
imz -- Ivan Zakharyaschev
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14
votes
2 answers
Very slow Chromium browser
On my machine Chromium is very slow, I had to switch to Firefox where everything works fine.
Looks like this is a kind of JavaScript problem (eg. slowed down typing on Facebook), pages loading slower, feels like the pages are heavy.
Is there any…
takeshin
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14
votes
1 answer
GDB crashes with: ImportError: No module named libstdcxx.v6.printers
I have a problem with GDB. Whenever I try to debug any C++ program, just after running it, GDB gives this error:
(gdb) run
Starting program: /home/errikos/Workspaces/tests/a.out
Traceback (most recent call last):
File…
ergysdo
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