kapstok / Post-mortem-debugging (public) (License: MIT) (since 2018-11-16) (hash sha1)
Simple sample on how post mortem debugging in C(++) works.
Clone URLs: https://rocketgit.com/user/kapstok/Post-mortem-debugging ssh://rocketgit@ssh.rocketgit.com/user/kapstok/Post-mortem-debugging git://git.rocketgit.com/user/kapstok/Post-mortem-debugging
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README.md:

Fault handling

When the application crashes, e.g. due to derefencing NULL, a dump will be made. The dump will be shown on the Terminal and will saved in a log file called /var/log/messages.

Compiling

> Commands executed from repository's root.

g++ main.c -o exe
g++ main.c -g -o dbgexe

Post mortem debugging

Running ./exe results in this output:

Error 11 at (nil):
Called from 0x400a48
Compiled at: May 30 2018 09:24:41
Aborted (geheugendump gemaakt)

In order to read the dump from the log file, while filtering all log info from other applications, one should execute the following command in a Terminal:

# cat /var/log/messages | grep "postmortem-debugging" | sed 's/#012/\n\t/g' | less

> Syslog turns newlines ('') in '#012'. The sed command reverts that.

Possible output would be:

May 30 09:38:14 localhost postmortem-debugging[14671]: Error 11 at (nil):
May 30 09:38:14 localhost postmortem-debugging[14671]: Called from 0x400a48.
May 30 09:38:14 localhost postmortem-debugging[14671]: Compiled at: May 30 2018 09:24:41

Let's see what caused the error by executing this one-liner:

$ gdb ./dbgexe

Then you need to use the information from the log file. Execute this code in gdb:

l *0x400a48

> Use the output from running ./exe ('Called from 0x400a48').

As gdb states, the error was caused at line 71:

0x400a48 is in main() (main.cpp:71).
Hints:
Before first commit, do not forget to setup your git environment:
git config --global user.name "your_name_here"
git config --global user.email "your@email_here"

Clone this repository using HTTP(S):
git clone https://rocketgit.com/user/kapstok/Post-mortem-debugging

Clone this repository using ssh (do not forget to upload a key first):
git clone ssh://rocketgit@ssh.rocketgit.com/user/kapstok/Post-mortem-debugging

Clone this repository using git:
git clone git://git.rocketgit.com/user/kapstok/Post-mortem-debugging

You are allowed to anonymously push to this repository.
This means that your pushed commits will automatically be transformed into a merge request:
... clone the repository ...
... make some changes and some commits ...
git push origin main