RE: pthread_exit bug ?

RE: pthread_exit bug ?

[Bossom, John]

Yes... Unless you call pthread_exit from the main line, you will
not have any of your thread-specific-destroy routines called for the
main-line.

(I believe this is documented in one of the PThreads books by Bil Lewis)


John.

-----Original Message-----
From: Milan Gardian [ mailto:mg@tatramed.sk ]
Sent: Thursday, September 02, 1999 6:36 AM
To: 'Tristan Savatier'; pthreads-win32@sourceware.cygnus.com
Subject: RE: pthread_exit bug ?


[snip]
> My program creates several threads.  At termination,
> each thread (except the main thread) terminates by calling
> pthread_exit, then the main thread terminates by
> calling pthread_exit (at this point, all my threads
> are terminated, therefore the process should disapear).

(This note does not try to diminish the meaning of the reported bug)
Q: Is there a reason to use pthread_exit from the main thread? A special
functionality prehaps? Specifically, I would like to know if there's some
difference between these two code snips:

(a)
int main(void)
{
    //Do some threading stuff...
    return (24);
}


(b)
void main(void)
{
    //Do some threading stuff...
    pthread_exit(24);
}

From the rather ideological reasons  :) I prefer the (a) version, but will
gladly learn if there's a point in the (b) version.

Looking forward to anyone answering;
Yours sincerely,
	Milan G.

RE: pthread_exit bug ?

[Milan Gardian]

[snip]
> My program creates several threads.  At termination,
> each thread (except the main thread) terminates by calling
> pthread_exit, then the main thread terminates by
> calling pthread_exit (at this point, all my threads
> are terminated, therefore the process should disapear).

(This note does not try to diminish the meaning of the reported bug)
Q: Is there a reason to use pthread_exit from the main thread? A special
functionality prehaps? Specifically, I would like to know if there's some
difference between these two code snips:

(a)
int main(void)
{
    //Do some threading stuff...
    return (24);
}


(b)
void main(void)
{
    //Do some threading stuff...
    pthread_exit(24);
}

From the rather ideological reasons  :) I prefer the (a) version, but will
gladly learn if there's a point in the (b) version.

Looking forward to anyone answering;
Yours sincerely,
	Milan G.

Re: pthread_exit bug ?

[Ross Johnson]

Tristan,

Please try pthreads-win32-snap-1999-08-12 with your code. It fixes a
bug in pthread_exit.

ftp://sourceware.cygnus.com/pub/pthreads-win32/dll-latest

I'm about to create a new snapshot so keep a lookout for that one
also.

Cheers.
Ross 

On Thu, 2 Sep 1999, Tristan Savatier wrote:

> I am currently using pthreads-win32-snap-1999-05-30,
> using VC++ 6.0 under Win98.
> 
> My program creates several threads.  At termination,
> each thread (except the main thread) terminates by calling
> pthread_exit, then the main thread terminates by
> calling pthread_exit (at this point, all my threads
> are terminated, therefore the process should disapear).
> 
> This works fine with native pthread libraries on
> Linux and other Posix systems.
> 
> But I noticed that with pthreads-win32, calling pthread_exit 
> to terminate my main thread does not work well: the process survives
> with two dangling threads (both threads are some type
> of internal kernel threads, not running any of my code).
> 
> If I call exit(0) [instead of pthread_exit] to terminate
> my main thread, the process terminates properly (i.e.
> this is a workaround).
> 
> This looks like a bug: the pthread standard says,
> in the pthread_exit specification:
> <<When the last thread in a process exits, exit(0)
> will be called.>>
> 
> Is that a known bug ?
> 
> -t
> 

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Re: pthread_exit bug ?

[Peter Slacik]

Tristan Savatier wrote:

> I am currently using pthreads-win32-snap-1999-05-30,
> using VC++ 6.0 under Win98.
>
> My program creates several threads.  At termination,
> each thread (except the main thread) terminates by calling
> pthread_exit, then the main thread terminates by
> calling pthread_exit (at this point, all my threads
> are terminated, therefore the process should disapear).
>
> This works fine with native pthread libraries on
> Linux and other Posix systems.
>
> But I noticed that with pthreads-win32, calling pthread_exit
> to terminate my main thread does not work well: the process survives
> with two dangling threads (both threads are some type
> of internal kernel threads, not running any of my code).
>
> If I call exit(0) [instead of pthread_exit] to terminate
> my main thread, the process terminates properly (i.e.
> this is a workaround).
>
> This looks like a bug: the pthread standard says,
> in the pthread_exit specification:
> <<When the last thread in a process exits, exit(0)
> will be called.>>
>
> Is that a known bug ?

Yes, I noticed this already and tried to find out possible workarounds, but
I forgot this problem later, because my application calls exit().

I'm not sure but I remember that last year's snapshots behaved correctly...

Peter Slacik

pthread_exit bug ?

[Tristan Savatier]

I am currently using pthreads-win32-snap-1999-05-30,
using VC++ 6.0 under Win98.

My program creates several threads.  At termination,
each thread (except the main thread) terminates by calling
pthread_exit, then the main thread terminates by
calling pthread_exit (at this point, all my threads
are terminated, therefore the process should disapear).

This works fine with native pthread libraries on
Linux and other Posix systems.

But I noticed that with pthreads-win32, calling pthread_exit 
to terminate my main thread does not work well: the process survives
with two dangling threads (both threads are some type
of internal kernel threads, not running any of my code).

If I call exit(0) [instead of pthread_exit] to terminate
my main thread, the process terminates properly (i.e.
this is a workaround).

This looks like a bug: the pthread standard says,
in the pthread_exit specification:
<<When the last thread in a process exits, exit(0)
will be called.>>

Is that a known bug ?

-t