class mutex

[jay.krell at cornell.edu]

No. Windows does not use a tempfile. That would be crude.

NT at least has an internal in-memory-mostly hierarchical namespace. The
file system and registry namespaces rooted in the in memory namespace. Lots
of different types of named objects can live in the namespace, and the
system is extensible (there's a toplevel directory \ObjectTypes). Types
include Type, Directory, Port, Device, Event (Win32/NT kernel event, same
thing), Mutant (something that an implement the semantics of both Win32
mutexes and OS/2 mutexes), SymbolicLink, Section (file memory mapping,
possibly pagefile backed), Process, Thread, Timer, Token (security), Driver,
File, Key (registry). Win32 objects live in \BaseNamedObjects, at least on
non Terminal Server logins.

Run winobj from www.sysinternals.com.

Win32 critical sections are much cheaper than Win32 mutexes.
Every mutex operation is a syscall.
Critical sections only involve syscalls when there is contention on them --
they on demand create a kernel object and wait on it.

 - Jay

-----Original Message-----
From: Olivier Dagenais <olivierS.dagenaisP at canadaA.comM>
Newsgroups: comp.lang.python
To: python-list at python.org <python-list at python.org>
Date: Sunday, October 22, 2000 6:16 PM
Subject: Re: class mutex


>MSDN says this about an article relating to CreateMutex:  "You can use a
>mutex object to protect a shared resource from simultaneous access by
>multiple threads or processes."  Does Unix/Linux also have something like
>this (at the process level)?  What about Mac and (maybe) other platforms?
>It would be nice if they were wrapped in one convenient Python
>module/object.
>
>It sounds like Windows uses a tempfile to accomplish this and I would guess
>Unix/Linux - a file-oriented OS - would do the same thing.  However, these
>are just guesses, we'd need to confirm this...
>
>--
>----------------------------------------------------------------------
>Olivier A. Dagenais - Software Architect and Developer
>"Someone called 'Type your name here' is impersonating me on the
>internet and is posting exactly the same things I am posting!"
>
>
>"Darrell" <news at dorb.com> wrote in message
>news:MUII5.70068$JS3.10348560 at typhoon.nyroc.rr.com...
>> If your on Windows then try "win32event.CreateMutex"
>>
>> --Darrell
>>
>> "Prof. Peter Stoehr" <peter.stoehr at weihenstephan.org> wrote in message
>> > Based on that, I have two questions:
>> > 1) Does python provide a real mutex object.
>> > 2) What is the use of the class mutex
>> >
>>
>>
>>
>
>
>--
>http://www.python.org/mailman/listinfo/python-list