From mboxrd@z Thu Jan  1 00:00:00 1970
From: ludo@gnu.org (Ludovic =?utf-8?Q?Court=C3=A8s?=)
Subject: Re: dmd: [PATCH] Improve socket connection errors handling.
Date: Thu, 10 Apr 2014 16:52:35 +0200
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References: <20140410081446.GF9248@kubera.prv.maison>
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To: Cyprien Nicolas <cyprien@nicolas.tf>
Cc: guix-devel@gnu.org

Cyprien Nicolas <cyprien@nicolas.tf> skribis:

> My first patch for dmd :-)

Very cool, welcome!  :-)

Those backtraces had been bothering me for a while too, so thanks for
looking at it.

> From 6e8f871198b661b631a319f3abaef71bc6269fb7 Mon Sep 17 00:00:00 2001
> From: Cyprien Nicolas <cyp@fulax.fr>
> Date: Thu, 10 Apr 2014 10:07:06 +0200
> Subject: [PATCH] Improve socket connection errors handling.
>
> If the user running `deco' does not have the rights privileges to open
> the unix socket, the raised exception produces a backtrace.
>
> * modules/dmd/comm.scm (open-connection): Add a (catch
>   'system-error...) guard around the connect function call.
>   The handler will abort the program in case of error.

I pushed a couple of patches that achieve the same result slightly
differently: =E2=80=98open-connection=E2=80=99 is left unchanged and it=E2=
=80=99s the caller=E2=80=99s
responsibility to handle any errors; clients use the new
=E2=80=98with-system-error-handling=E2=80=99 macro do handle all =E2=80=98s=
ystem-error=E2=80=99
exceptions gracefully.

One remark:

> +        (lambda (key . args)
> +          (display (format #f "Error: Cannot connect to socket `~a': ~a\=
n"
> +                           file (apply format #f (cadr args) (caddr args=
)))
> +                   (current-error-port))

This could be directly (format (current-error-port) ...).

Also, we avoid uses of =E2=80=98car=E2=80=99, =E2=80=98cadr=E2=80=99 etc. i=
n favor of =E2=80=98match=E2=80=99 (at least
in new code.)

Thanks!

Ludo=E2=80=99.