[toonarific]

I just recently had my hosting company install gdb onto my server. I am running a mud on one of my IPs, that occassionally crashes. How do I create a coredump file to review it to see what is causing the crash? I havent used gdb before, and cant seem to find the right command to generate the coredump file

[toonarific]

*bump*

Does anyone know how to make these coredump files?

[AGCurry]

Originally Posted by toonarific

*bump*

Does anyone know how to make these coredump files?

I almost tried to answer this question a few days ago but decided I didn't know enough about it.

In general, a core dump is created whenever a program has a fatal memory error. However, I don't know how you would prompt a core dump from "the outside" except by using the "kill" command. From WITHIN the program, the abort() function will do it - or, of course, you can purposely code something dangerous - like copying a string to a null pointer - and see if that works.

And, of course, the owner of the process must have write permission on the directory and on any existing core files...

That's about all I know.

[lotuseclat79]

Originally Posted by toonarific

I just recently had my hosting company install gdb onto my server. I am running a mud on one of my IPs, that occassionally crashes. How do I create a coredump file to review it to see what is causing the crash? I havent used gdb before, and cant seem to find the right command to generate the coredump file

Hi toonarific,

First, read the man page on gdb, i.e. issue the command: man gdb

Next, you will at least have to run the "mud" under gdb for it to be useful, or execute gdb and attach it to the "mud" process.

A few key things about using gdb to debug software is:
1) was the program "mud" compiled with symbols or were they striped out of the executable
2) is the source code for the "mud" available or are you working from an executable only

Sometimes, simply running: gdb mud
and then starting up gdb to run the program may be all you need to do, i.e. by running the program until it crashes in gdb for you, but from what you say you want it to output a core dump - you should check out the GDB manual online for information on doing that. See: http://www.gnu.org/software/gdb/documentation/

Run ulimit -a to see if the core file size output is unlimited or set to zero.

-- Tom