How to create a core dump even if the process is normally running?

Question

Under Linux, when a process crashes, a core dump will be created.

However, I want to create a core dump when the process doesn't crash, but looks buggy. A remote expert need the core dump to analyze.

Under Windows, we can create a dump file of a process through task manager, and after that, the process is still running.

Is it possible under Linux?

score 23 · Accepted Answer · answered Dec 21 '14 at 03:26

23

Call gdb, then

attach pid
gcore

where pid is the process id of the process in question.

answered Dec 21 '14 at 03:26

Wintermute

score 17 · Answer 2 · answered Dec 21 '14 at 12:38

17

You can use gcore utility right from command line:

gcore [-o filename] pid

By the way, if you want to see only stack trace of the process, gstack utility will do the job.

Both utilities come with gdb.

answered Dec 21 '14 at 12:38

Evgeny Kluev

score 14 · Answer 3 · answered Dec 21 '14 at 07:55

14

You can do it within your code with:

if (fork() == 0) abort();

answered Dec 21 '14 at 07:55

Marian

5

This likely isn't the best solution but boy is it clever :) – Benjamin Gruenbaum Dec 21 '14 at 11:34

score 9 · Answer 4 · answered Dec 21 '14 at 03:48

If you want to do this programmatically, try using google-coredumper. Their example:

#include <google/coredumper.h>
...
WriteCoreDump('core.myprogram');
/* Keep going, we generated a core file,
 * but we didn't crash.
 */

4 Answers4