12:18 <lightydo> Hi, does anybody have an idea on detecting process daemonization with stap? I would like to avoid detecting the whole general guidelines for daemonization, i.e. umask, fork, setsid etc..but rather detect when a process's ppid and sid have changed...

14:20 <drsmith> lightlydo: Hmm, interesting. I had a quick look around kernel/exit.c, and I'd suggest probing reparent_leader() and/or forget_original_parent(). Those might get you what you want.

15:01 <lightydo> drsmith: thanks that was also my first lead....looking into it.

15:08 <lightydo> drsmith: only problem so far is that both are static functins, hence no script level local variables

15:08 <drsmith> but you do have the args, right?

15:11 <lightydo> not according to stap -L

15:12 <drsmith> I see the args on 4.15.6-300.fc27.x86_64

15:13 <drsmith> it looks like exit_notify() might be the next candidate up the stack

15:13 <lightydo> doesn;t that depend on the stap version? (mine is version 3.2/0.170, commit release-3.2-0-g4051c70c9318 + changes)

15:13 <drsmith> possibly, but it mostly depends on the debuginfo

15:14 <drsmith> I'm running HEAD

15:15 <fche> we should have context variables for it

15:16 <lightydo> same for exit_notify....I am testing on Ubuntu 17.10 (4.13.0-36-generic) but I will need this on various systems from as old as 2.6

15:17 <fche> right, you will need dbgsyms stuff for $context variables

15:17 <fche> ubuntu's come some way in making those available, but still not as smooth as fedora

15:19 <lightydo> I have dbgsyms but as you say, probably not enough...

15:20 <drsmith> make sure you dbgsyms are for your *exact* kernel version

15:26 <lightydo> will look into it...logging off..

15:36 <fche> lightydo, stap-prep may help.