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From: Ryan Bloom <rbb@covalent.net>
Reply-To: rbb@covalent.net
Organization: Covalent Technologies
To: Ian Holsman <ianh@cnet.com>,
	Justin Erenkrantz <jerenkrantz@ebuilt.com>
Subject: Re: [PATCH] Add reentrant gethostbyname call
Date: Thu, 19 Jul 2001 20:22:23 -0700
Cc: dev@apr.apache.org
References: <20010719193655.K324@ebuilt.com> <3B579D80.90101@cnet.com>
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On Thursday 19 July 2001 19:54, Ian Holsman wrote:
> Justin Erenkrantz wrote:
> >During some testing with flood (~30 threads), we ran into a stack
> >corruption error in our code.  We tracked it down to the fact that
> > we were using a non-reentrant version of gethostbyname.  This
> > patch lets us call the reentrant version of gethostbyname and now
> > we haven't been able to recreate the segfault.
> >
> >The only possible optimization would be the size of the temporary
> >buffer (currently 256).  Roy mentioned that the address array in
> >hostent has a maximum of 10 entries.  If so, the size of the
> >structure plus the maximum size of the array (10 entries) may be
> >sufficient.  If we send in a too small buffer, we should
> >receive ERANGE.
>
> Is there a reason why we shouldn't just use the re-entrant versions
> where it is available?

It can be overhead that we don't need, it all depends on how the 
re-entrant version is implemented.

> >Any reason we shouldn't commit?  -- justin

You can't check for threads that way.  You need to use the same basic 
logic that we use in dir.c to check for readdir_r.

Ryan