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Date: Fri, 15 Sep 2006 15:23:16 -0400
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Subject: Re: [PHP-DEV] Two modules w/ different instances of same lib causes
 crash
From: mba2000@ioplex.com (Michael B Allen)

RTLD_DEEPBIND fixes this problem using a test program and two minimalistic
DSOs to emulate the namespace clash problem. But I see PHP has support
for RTLD_DEEPBIND:

# if defined(RTLD_GROUP) && defined(RTLD_WORLD) && defined(RTLD_PARENT)
...
# elif defined(RTLD_DEEPBIND)
...
# else
...
# endif

On my Linux glibc 2.3 systems RTLD_DEEPBIND is chosen.

So now, I have to wonder why my customer had a problem in the first place.

Based on the above macros, is it possible that RTLD_DEEPBIND could NOT
be chosen?

Mike

On Fri, 15 Sep 2006 11:43:56 -0400
Michael B Allen <mba2000@ioplex.com> wrote:

> My extension (plexsso.so) is dymanically linked with a library. That
> library (libplexsso.so) is a statically linked collection of libs
> including a custom version of Heimdal Kerberos (libkrb5.a). I have found
> that if another module is linked with the stock Heimdal (e.g. pgsql.so
> dynamically in this case) some symbol mixing occurs and the application
> crashes.
> 
> Can two modules use different instances of the same library?
> 
> Before I go try to become an expert in linking and the Linux loader
> can anyone give me advice as to how to I might workaround (for Linux
> at least)?
> 
> Mike

-- 
Michael B Allen
PHP Active Directory SSO
http://www.ioplex.com/