Mutex - does it work?

Scripting
1

Has anybody successfully used Mutex in C#?

I am asking because I have a piece of code that uses locking/unlocking with a Mutex object but occasionally crashes and the crash clearly indicates that there is no mutual exclusion in the code.

Thanks.

2

threading etc in mono 1.2.5 (as used in unity 2 / unity iphone 1.x) is quite a bit broken.

also mutex won’t help you in case you think about letting an external thread call into unity stuff as unity does not respect nor use mutexes.

3

If that is the case, how can one use any kind of thread as part of a system?

I have a situation where I use a UDP class to read packets from an external server. The UDP reader is a separate thread because it uses blocking reads.

The problem is, you cannot do Unity things in a thread (such as creating a game object) so I gather all messages in a list and let the regular Update() call implement the actions.

I need a synchronization mechanism to ensure that the background thread does not write the list while the Update code is reading it.

Is there a different way to achieve this without using some kind of lock?

4

as you commonly would do it in C# I guess:

lock(some System.Collections.* adt)
{
  ... perform ops ...
}

mutex should work too if you prefer that, as long you have code that works smart there … and keep in mind, the price of mutex is that your whole game will freeze until the lock / mutex has been passed

5

Yes, we do.

We use Mutex in our game, and it seems all ok until I upgraded to 3.0 today. My web player build totally fails on “new Mutex()”. But the standalone version works well.

No solution so far.

6

Well, that answers my question from a few minutes ago. I just ran into this problem myself. “new Mutex()” fails in the web player.

7

Locks work fine in background threads in 3.0. Never tried Mutex