I notice than applications launched using dmenu doesn't have the double fork.  I changed the terminal=urxvt  to  terminal="exec urxvt" (as in dmenu key binding) and also I don't have double-fork.

 2190  2033  09:36  \_ /home/superman/.xmonad/xmonad-i386-linux
10259  2190  10:32      \_ /bin/sh -c urxvt
10260 10259  10:32      |   \_ urxvt
10261 10260  10:32      |       \_ bash
10286 10261  10:32      |           \_ ssh sumerman@kriptongo.es
12482  2190  10:49      \_ urxvt
12493 12482  10:49          \_ bash
14711 12493  11:06              \_ ps -fea --forest

I'll worth to change spawn and automatically add exec to command string?

On Wed, Dec 2, 2009 at 4:36 AM, Spencer Janssen <spencerjanssen@gmail.com> wrote:
> On Tue, Dec 01, 2009 at 07:07:48PM +0100, Luis Cabellos wrote:
>> Hi, I was checking why there is two procces every time than I launch a
>> console. I found than spawn uses /bin/sh to lauch applications. I
>> think than to expecific commands is no need to double-fork,
>>
>> I added the patch lo launch console without double-fork:
>
> [elided]
>
>> What do you think?
>
> spawnPIDf won't with applications that take arguments, for example:
>
>    spawn "xset -b"
>
> I think the best solution is to add an 'exec' to your spawned applications:
>
>    spawn "exec xterm"
>
> This is the shell's syntax to execute a program directly rather than fork.
>
> The current implementation seeks to balance all of these concerns:
>  * users want to supply arguments to programs
>  * users will find "spawn prog [arg1, arg2, arg3]" syntax unwieldy
>  * we don't want to support a homebrewed argument tokenizer in xmonad
>  * some users will want to use shell syntax in their spawns
>
>
> Cheers,
> Spencer Janssen
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>



--

LC, ("Prefiero caminar con una duda, que con un mal axioma." - Javier Krahe)