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From: Ian Collins <ian-news@hotmail.com>
Newsgroups: comp.programming.threads
Subject: Re: Is pthread_create( id, 0, f, &something_on_my_stack ); safe?
Date: Mon, 21 Nov 2011 20:00:35 +1300
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On 11/21/11 04:29 PM, Johann 'Myrkraverk' Oskarsson wrote:
> Hi all,
>
> Given
>
>    void *f( void *j )
>    {
>      int i = *((int *)j);
>      //..
>    }
>
>    void g( void )
>    {
>      pthread_t *id = ...;
>      int something_on_my_stack = 42; // Life, universe&  everything
>      pthread_create( id, 0, f,&something_on_my_stack );
>
> is there any guarantee the value has been copied to f()s stack by the
> time pthread_create() returns?

No.

> Or, to be a little bit more explicit, is there anything I can use for
> safe argument passing to newly created threads without allocating new
> memory and (presumably) have the threads free it?

I can't see any problem with

static int something_on_my_stack = 42;

-- 
Ian Collins