Debugging browser crash via CLI

Question

I'm preparing for an interview and came across this question in a forum:

If your browser crashes, how would you debug it only using the command line?

For simplicity, let's assume it's a Firefox browser on a *nix environment. Any suggestions would be helpful.

Answer 1

When they say crashed browser are we talking about an actual bug in firefox or a plugin that results in a crash?

Debugging is possible, but it assumes a developer experience.

Use ulimit -c to make sure your system will actually create a core dump with the application crashes. Then use GDB (*nix) to debug. You will probably want to download the source code for the browser. You may want to recompile your browser with the debug symbols.

Unless the question is for a developer position though I doubt you would be expected to be able to do this.

Are you sure they are asking how to debug a crashed browser, or are they talking about finding a network issue which should be very easy to diagnose from a command line. In that case you would be using something like ping, nslookup, traceroute, and so on.

See: https://developer.mozilla.org/en/Remote_debugging#Core_dumps_on_Mac_and_Linux

Answer 2

On Linux, for general purpose debugging, especially for an application that you don't have the source for, try strace and or ltrace. There's a good basic introduction to strace here. There are similar programs for windows.

strace firefox