> -----Original Message----- > From: [email protected] [mailto:rsyslog- > [email protected]] On Behalf Of [email protected] > Sent: Tuesday, July 19, 2011 9:07 AM > To: rsyslog-users > Subject: Re: [rsyslog] linking from dlloaded modules to global symbols > > I have access to SIX (and one of these day's I'll get a chance to try > to > get rsyslog to compile there again) > > can you make a short test program for me to compile there? I know I > have > AIX 5.3 and 6.1 available, and I think I have 5.2 available.
Thanks - I'll try ASAP, but it may take me few days as I think it is not totally trivial (need to fiddle with autotools, create new project etc -- not just a simple program). Rainer > > David Lang > > On Tue, 19 Jul 2011, Rainer Gerhards wrote: > > > Date: Tue, 19 Jul 2011 08:58:30 +0200 > > From: Rainer Gerhards <[email protected]> > > Reply-To: rsyslog-users <[email protected]> > > To: rsyslog-users <[email protected]> > > Subject: [rsyslog] linking from dlloaded modules to global symbols > > > > Hi all, > > > > I have a question to which some of you may have at least an opinion. > > > > A couple of years ago, I read in several guides and textbooks that > there > > potentially is a problem in this situation: > > > > Let a, b be dlloaded modules. Let a.a and b.b be public symbols in > these > > modules, and g.g a public symbol inside rsyslog core (which loads a > and b). > > Now assume code in b wants to access a.a and g.g (so the dlloaded > module > > needs to resolve public symbols inside the core and other dlloaded > modules > > during its load time). Linux handles this without problems, and as it > looks > > Solaris and BSD do as well. However, I was told that there are some > platforms > > which do not support this (AIX? HP-UX?). > > > > In order to keep portable, I created a scheme where b (the dlloaded > module) > > queries pointers to all other methods in core and dlloaded modules it > needs. > > This works well, but there is some overhead associated with that. > Obviously, > > there is a (mild) runtime overhead. But it also causes development > overhead, > > as quite some code needs to be written to support that. > > > > Looking backward, I have never seen any platform that actually > requires that > > scheme. Even "better", I have not followed it in all cases (some > legacy > > calls) and I never got into any troubles. May be that's just because > I don't > > have AIX and HP-UX and ... > > > > The big question is if it really makes sense to continue that way. If > we can > > conclude that the problem this code intends to solve is actually no > problem, > > I could clean up a lot of code and also get some better development > > productivity in the future. Also, as far as I know, libtool permits > static > > module linking for such cases if a very exotic platform would > actually not > > support the dynaload functionality. > > > > So I am pretty tempted to drop that approach and use the Linux > dynalinker's > > capability. Does anyone have concerns about this? Does it sound > reasonable? > > > > Feedback would deeply be appreciated. > > > > Thanks, > > Rainer > > _______________________________________________ > > rsyslog mailing list > > http://lists.adiscon.net/mailman/listinfo/rsyslog > > http://www.rsyslog.com > > > _______________________________________________ > rsyslog mailing list > http://lists.adiscon.net/mailman/listinfo/rsyslog > http://www.rsyslog.com _______________________________________________ rsyslog mailing list http://lists.adiscon.net/mailman/listinfo/rsyslog http://www.rsyslog.com
