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Date: Fri, 21 Nov 1997 15:22:01 -0600 (CST)
From: Alex Nash <nash@Mcs.Net>
To: Curtis Bray <cbray@best.com>
cc: freebsd-hackers@freebsd.org
Subject: Re: malloc() problems in children after using rfork()
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On Fri, 21 Nov 1997, Curtis Bray wrote:

> Hi,
> 
>   I'm trying to use rfork(RFPROC | RFMEM) so that all the children can
> share the same address space with their parent.  
> 
>   If I have multiple children issuing mallocs the children seem to core
> dump.  Once I turn the RFMEM flag off I have no problem mallocing (but
> of course I loose the shared address space).  Anyone know what I could
> be doing wrong here?  Do I have to put semaphores around every malloc?? 
> I hope that's not the case...  Thanks in advance!

The only locking malloc() performs is pthread_mutex_lock/unlock in the
libc_r version.  The non-threaded version provides no locking at all.

Alex