Subj : Re: simple: passing a pointer to a handle to another thread
To   : comp.programming.threads
From : Ulrich Eckhardt
Date : Fri Sep 09 2005 08:30 am

LeftHorn wrote:
> i have a main() function where i creates a class.

No, you don't, you create an instance of a class, an object.

> then i have a thread, where when initiated i pass the pointer (in the 
> params) to this class (among other things).
> 
> Inside this thread i i then access this object through a pointer, an 
> one of the functions is a function that returns a handle to a Semaphore.
> 
> But when doing that - i get an error "access overrun" attempt to access 
> local block - when i have the class generated inside the thread, there 
> is no problem.

Could you please post the whole error-message and when exactly it happens?
Other than that, look at the pointer you want to pass into the thread
function and the pointer that arrives there, are they equal?

> How can i share a handle that isnt global among threads ?

If something is intended to be thread-local, you probably shouldn't. I know
that the MFC make some use of thread-local storage and because of that you
can't use CWnd objects across threads.

Uli

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