Singleton process
Benjamin Han
bhan at andrew.cmu.edu
Mon Dec 22 01:38:27 EST 2003
But this solution creates a file race condition?
Also I just realized that lock (via fcntl.lockf() ) is actually not useful
since in this case scripts will come and go - locks will be lost whenever
a process terminates.
There should a code pattern for this - any more ideas? Thanks!
On Mon, 22 Dec 2003, Jp Calderone wrote:
> On Sun, Dec 21, 2003 at 09:38:49PM -0800, Fortepianissimo wrote:
> > Here is the situation: I have multiple processes of same Python script
> > fired, but I want *only one* of them to continue and all the others to
> > quit immediately.
> >
> > I can use a lock file, and the first process will get the necessary
> > lock. But if I do open(lockfile) all the other subsequent processes
> > will just wait there - instead I want them to quit immediately.
> >
> > Can someone give a simple outline of how to achieve this? Thanks a
> > lot.
>
> import os, errno
>
> def shouldRun():
> try:
> os.mkdir(MAGIC_PATH)
> except OSError, e:
> if e.args[0] == errno.EEXIST:
> return False
> raise
> return True
>
> Jp
>
More information about the Python-list
mailing list