Cleaning up after C module

[j1k1cki]

Hello,

I have a Python module written in C that spawns and kills processes
using OS-specific mechanisms. I want to kill all spawned processes when
the interpreter exits. I tried to wrap every spawned process in a
Python object like this:

import cmodule
class Process:
__init__(self, execname): self.pid = cmodule.spawn(execname)
__del__(self): cmodule.kill(self.pid)

p = Process("foo")

but this does not work, I am getting and exception inidicating that
'cmodule' is 'None' in '__del__()'.

Moreover, the Language Reference states that "It is not guaranteed that
__del__() methods are called for objects that still exist when the
interpreter exits", so it looks like this approach is wrong anyway. How
do I do this right?

Thanks very much in advance
Grzegorz

PS: Python 2.3.3

 

[Fredrik Lundh]

I have a Python module written in C that spawns and kills processes
using OS-specific mechanisms. I want to kill all spawned processes when
the interpreter exits. I tried to wrap every spawned process in a
Python object like this:

import cmodule
class Process:
__init__(self, execname): self.pid = cmodule.spawn(execname)
__del__(self): cmodule.kill(self.pid)

p = Process("foo")

but this does not work, I am getting and exception inidicating that
'cmodule' is 'None' in '__del__()'.

module-level names may be cleaned away before your objects, so if you want
to make sure you can reach a module-level object, create your own binding:

def__del__(self, cmodule=cmodule): cmodule.kill(self.pid)

Moreover, the Language Reference states that "It is not guaranteed that
__del__() methods are called for objects that still exist when the
interpreter exits", so it looks like this approach is wrong anyway. How
do I do this right?

the "atexit" module might be what you need.

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