bug#64455: shepherd: unable to use redefined system/system* in 0.10.1

["Ludovic Courtès" <ludo@gnu.org>]

Hi,

"buma2023@outlook.fr" <buma2023@outlook.fr> skribis:

> I am using happily shepherd since a few years as my init system on
> Debian: amd64 (desktop and notebook), armhf (Cubox).

Interesting!  I didn’t know of such uses.

> I was using 0.9.1 with guile-3.0.5 and fibers-1.1.1.
>
> I recently tried 0.10.1 with guile-3.0.9 and fibers 1.3.1 and
> encountered a problem with using system and system* in my services:
> the simple fact to have the symbol system or system* in
> /etc/shepherd.scm or included files (even if the command is not
> executed) leads to a misbehaving shepherd, more specifically the
> shepherd socket disappears; the system boots but with multiple
> instances of the launched daemons.
>
> If a system/system* command is executed while booting, shepherd
> blocks at the point of its execution.
>
> Example of service causing the failure:
>
> (register-services
>  (make <service>
>    #:provides '(mytest)
>    #:start (lambda args
>            (system "touch /tmp/somefile")
>            #t)
>    ))
>
> The service is not started at boot, I have to do it manually afterwards,
> but I never can go there, as the shepherd socket is missing.

I can reproduce it like this:

--8<---------------cut here---------------start------------->8---
$ cat /tmp/t.conf
(register-services
 (make <service>
   #:provides '(mytest)
   #:start (lambda args
             (system "touch /tmp/somefile")
             #t)))

(start 'mytest)
$ shepherd -I -c/tmp/t.conf -s /tmp/sock 
Starting service root...
Service root started.
Service root running with value #t.
Service root has been started.
Starting service mytest...
  C-c C-z
[1]+  Stopped                 shepherd -I -c/tmp/t.conf -s /tmp/sock
$ bg
[1]+ shepherd -I -c/tmp/t.conf -s /tmp/sock &
$ herd -s /tmp/sock status
herd: error: /tmp/sock: Connection refused
--8<---------------cut here---------------end--------------->8---

This is both with 0.10.1 and with
d5ed516e736ce473902cc86b5cf4f61f27ebb642.

To be continued…

Ludo’.