[Tutor] *nix-specific Python Scripting [Off Topic]

[ZIYAD A. M. AL-BATLY]

On Thu, 2005-05-12 at 13:37 -0400, William O'Higgins wrote:
> I am trying to learn Python by translating some of my Perl scripts.  One
> thing that is eluding me is assigning the results of system calls to
> variables.  Here's what I want to do in Perl:
>     
>     $isxrunning = `ps -C startx | grep "startx"`;
>     
>     if ($isxrunning =~ "startx") {
>         do something;
>     } else {
>         do something else;
>     }
>             
> It is a simple check to see if the X server is running (this is
> inelegant, but it works - if you have a better way, I'd love to know
> about it, but I would like to be able to do things like this in Python -
> so I might better write scripts with it).
> ...
(This is off topic! Sorry.)

Why using “ps -C startx | grep "startx"”?  Why not “ps h -C startx”[1]?
Even better, why not “pidof startx”?

As for another way to check for X, did you try checking for the lock
file? (Usually in “/tmp/.X0-lock”)  Combined with checking the $DISPLAY
environment variable, this is a much better and elegant solution in my
not-so-experienced opinion.

Notes:
     1. This probably wont work with FreeBSD (and all other *BSD(s) in
        that matter), instead, try the “--no-headers” option.  See the
        manual page for “ps”.

Ziyad.