Re: [Sheflug] core files?

["Chris J/#6" <nospam [at] nccnet.co.uk>]

> hi all,
> 
> in all the time i've been messing with linux, i've only come accross core files
> occationally. when i ran suse, they were automatically deleted after a while.
> 
> question......
> what are they and what are you suposed to do with them?
> 

When a program crashes in certain conditions (eg segmentation fault 
(SIGSEGV), or recieving an abort (SIGABRT)), a core file may be created. This 
file contains the programs state and the contents of memory it was using at 
the time of the crash. A developer can use the core file with a debugger, 
such as gdb, to locate where the crash happened and also why it happened. A 
list of signals at what the action the kernel takes by default (ie, does it 
create a core file or do something else, though many signals can be 
overridden programmatically) can be found by typing "man 7 signal".

Unless you're planning on debugging a program, they can be safely deleted 
with no ill effect. Most dists have a cron job that runs every now and then 
that deletes core files of a certain age.

On many shells, you can restrict the creation of core files by typing 
something akin to: "ulimit -c 0". Or, as I used to do on my old Uni accounts, 
symlink core to /dev/null :)

Chris...



-- 
Chris Johnson            \  "If not for me then, do it for yourself. If not
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