Subject: Re: bug#49839: [PATCH] shepherd: add keep-tty flag to skip setsid
From: Ludovic Courtès <[email-masked]>
To: muradm <[email-masked]>
Cc: [email-masked]
Date: Tue, 10 Aug 2021 14:51:51 +0200
List-Id: <debbugs-submit.debbugs.gnu.org>

Hi,

muradm <[email-masked]> skribis:

> * modules/shepherd/service.scm: add keep-tty flag to skip setsid
>
> when using shepherd as user, programs like xorg server, potentially
> any
> program which ends up interacting with user, require terminal to
> remain.
>
> currently, setsid is called unconditionally from exec-command
> function,
> making it impossible to have such process.
>
> this adds keep-tty flag to make-forkexec-constructor up to
> exec-command
> function where setsid is actually called.
>
> diff --git a/modules/shepherd/service.scm b/modules/shepherd/service.scm
> index 587ff68..1ae9544 100644
> --- a/modules/shepherd/service.scm
> +++ b/modules/shepherd/service.scm
> @@ -786,6 +786,7 @@ daemon writing FILE is running in a separate PID namespace."
>                         (log-file #f)
>                         (directory (default-service-directory))
>                         (file-creation-mask #f)
> +                       (keep-tty #f)
>                         (environment-variables (default-environment-variables)))
>    "Run COMMAND as the current process from DIRECTORY, with FILE-CREATION-MASK
>  if it's true, and with ENVIRONMENT-VARIABLES (a list of strings like
> @@ -804,7 +805,7 @@ false."
>      ((program args ...)
>       ;; Become the leader of a new session and session group.
>       ;; Programs such as 'mingetty' expect this.
> -     (setsid)
> +     (unless keep-tty (setsid))

I did that slightly differently:

  https://git.savannah.gnu.org/cgit/shepherd.git/commit/?id=c43f81794344dbac31bcb8b8f1c0d266f47f14fa

Let me know if it works for you.

Thanks,
Ludo’.