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kstart child PID
Hi .
I am writing an editor for Linux for the POV-RAY raytracer (with wxpython GUI).
When the user clicks on render I use 'kstart --ontop povray ...' to launch the render on top. The problem is that I need to know the PID of povray to read the output.
I get the PID of kstart ( that dies when povray is started ), but I do not get the child PID.
Does anyone have an idea ?
Thanks
fabien
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Maybe running a script and having it write the PID to some temporary file or a pipe.
Cheers,
_
Qt/KDE Developer
Debian User
Yes but how do you get the PID number of the app launched by kstart ?
fabien
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When writing the PID of the real program into a file inside the script, the PID of the script doesn't matter, does it?
Cheers,
_
Qt/KDE Developer
Debian User
with the python script below :
f=popen2.Popen4('kstart --ontop povray +itest.pov',1)
az=f.pid
az returns the PID number of kstart, not the PID NUMBER of povray
whereas with
f=popen2.Popen4('povray +itest.pov',1)
az=f.pid
az returns the PID number of povray.
I need to know the PID number to check whether the render is still running and to read the output stream.
Thanks
fabien
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So are you ignoring my initial suggestion or did I just not get through that you ought to start a script instead of povray and have the script write the PID into a file or PIPE?
Cheers,
_
Qt/KDE Developer
Debian User
Sorry, but I do not understand ( back from work, dumbness overwhelms me)...
What do you suggest ?
Sure, I can use a script that writes the child PID into a pipe, but I just do not know how to retrieve it.
with this command...
f=popen2.Popen4('kstart --ontop povray +itest.pov',1)
kstart spawns a child, but I cannot get the PID of its child.
If you have even a tiny script, please enclose it.
Thanks for enduring this.
Fabien
fabien
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Originally posted by fabienhenon
with this command...
f=popen2.Popen4('kstart --ontop povray +itest.pov',1)
f.pid ?
Originally posted by fabienhenon
What do you suggest ?
Sure, I can use a script that writes the child PID into a pipe, but I just do not know how to retrieve it.
By reading the file/pipe?
For example in bash you can do this
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Source code
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povray $@ &
echo $! > $(kdeconfig --path tmp)/povray.pid
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Then read povray.pid from the KDE tmp location
I guess an advanced script language like Python can do this as well.
Cheers,
_
Qt/KDE Developer
Debian User
Hi,
With the script below :
povray $@ &
echo $! > $(kdeconfig --path tmp)/povray.pid
I can get povray pid
With the script below :
kstart povray $@ &
echo $! > $(kdeconfig --path tmp)/povray.pid
I can get kstart pid, not povray pid (and that is what I want)
Cheers,
Fabien
fabien
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Originally posted by fabienhenon
With the script below :
kstart povray $@ &
echo $! > $(kdeconfig --path tmp)/povray.pid
I can get kstart pid, not povray pid (and that is what I want)
Obviously, as you
again use povray as the command for kstart instead of the script.
Do you think creating a script and putting it somewhere help when you don't change the command you are calling?
Cheers,
_
Qt/KDE Developer
Debian User
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Quoted
Originally posted by fabienhenon
Wednesday, April 24th 2024, 1:16pm
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