Re: [dwm] dwm-5.3

On Sat, 6 Dec 2008 19:20:58 +0100
Guillaume Quintin <coincoin169g_AT_gmail.com> wrote:

> On Sat, 06 Dec 2008 09:26:25 -0700
> Neale Pickett <neale_AT_woozle.org> wrote:
>
> > Jeremy Jay <dinkumator_AT_gmail.com> writes:
> >
> > > This was my hunch too, glad someone got it before me though. This
> > > patch fixes the problem with 5.3. Probably the same with the
> > > double- fork version too.
> >
> > The open FD was my first guess too, but the double-fork version
> > didn't close any fds either, so I assumed it must be something else.
> >
> > Guillaume, if you apply the "close(0)" patch, does the problem go
> > away?
> >
> > I'm away from my dwm computer right now, or I'd try it myself.
> >
> > Neale
> >
>
> I just tried the close(0) patch but it does not change anything. And I
> found something very weird. I told you that in the previous version of
> dwm (5.2) with the .xinitrc containing the "while | dwm" all worked
> fine and I am sure of that. I quitted dwm-5.2 many times with a lot of
> openned windows and all worked fine. But now, when I reinstall
> dwm-5.2 I get the same problem than in dwm-5.3 and dwm-5.3.1,
> "double-fork", "simple-fork" and re-"double-fork". I don't understand
> why.
>
> Why don't we change the way dwm gets its status text ? For example
> we could use the SIGALRM signal to call a "spawn2" :
>
> spawn2()
> {
> check for a certain shell script ".dwmstatus";
> if it is not present then return;
> create some pipe p[];
> (double or simple)-fork;
> in the child process
> {
> close(0);
> close(1);
> close(2);
> set stdout to p[1]; /* I don't know how exactly */
> execv(".dwmstatus");
> }
> /* Here is dwm */
> read status from p[0];
> display status;
> }
>
> This will take only a few LOC, because all the reading p[0] part
> will be in fact the reading-stdin code from the run() function which
> will not be needed anymore. This has the advantages that one can
> change the status when dwm is running and there are no more "quitting"
> problem. This is just an idea, forgive me not to propose some real
> code. Well tell me what you think of this idea.
>

This is more simple with the popen() function. We could simply get the
shell commands to execute from the arguments passed to dwm or read them
from any file or from stdin only once.

-- 
Kind regards,
Guillaume Quintin.