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help mutex

i want to be sure that only one instance of my script is running at the same
time
i try this little script

#---------------------------------------------------------------------------
# -*- coding: cp1252 -*-

from win32event import CreateMutex
from win32event import ReleaseMutex
from win32api import GetLastError
from winerror import ERROR_ALREADY_E XISTS
from time import sleep

mutex = None

attendre = True
while attendre:
mutex = CreateMutex ( None, 1, 'monmutexbienam oi' )
if (GetLastError ( ) == ERROR_ALREADY_E XISTS):
print 'another instance is running, i'm waiting'
sleep(10)
else:
attendre = False
print 'no instance, i'm running'

for i in range(10000):
print 'i'm working...'

# release the mutex
print 'release mutex %s. another instance could run' %mutex
ReleaseMutex( mutex )
#--------------------------------------------------------------------------

but it doesn't work when i launch multiple instance of my script.
the first one is running without problem.
The other one are waiting and are never released.

where is the trap ??
Didier
Jul 18 '05 #1
1 2668
> but it doesn't work when i launch multiple instance of my script.
the first one is running without problem.
The other one are waiting and are never released.

where is the trap ??


I think you should not try to create, but to actually *lock* the mutex. Then
the other scripts are blocked, until the first one executes. Then the next
one gets access.

I have no w32-api here, but at least thats what I remember from my old days
writing com-objects in C++....

Diez
Jul 18 '05 #2

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