Subject: Re: shepherd logging

From: [email-masked] (Ludovic Courtès)
Date: Sat, 17 Feb 2018 17:25:07 +0100

Danny Milosavljevic <[email-masked]> skribis:

> Oops, didn't see /var/log/shepherd.log - but I think it should just
> use syslog for that - and it's possible to use syslog for that by
> writing to /dev/kmsg .
>
> Does the Hurd with /dev/kmsg ?

It doesn’t have /dev/kmsg, but it has /dev/klog:

--8<---------------cut here---------------start------------->8---
ludo@darnassus:~$ ls -l /dev/klog 
crw-rw---- 1 root root 0, 0 Jul 16  2015 /dev/klog
ludo@darnassus:~$ showtrans /dev/klog 
/hurd/streamio kmsg
--8<---------------cut here---------------end--------------->8---

> How do they solve early boot logging ?

GNU Mach has a special “console” device that early boot processes can
open and write too, as in:

  https://git.savannah.gnu.org/cgit/hurd/hurd.git/tree/startup/startup.c#n731

It’s comparable to /dev/kmsg, but it exists before file system servers
are brought up, which is why it doesn’t have an entry in the file
system hierarchy.

Ludo’.