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From: Florian Weimer <fweimer@redhat.com>
To: Zack Weinberg <zackw@panix.com>
Cc: GNU C Library <libc-alpha@sourceware.org>
Subject: Re: dlinfo for the calling shared library
References: <CAKCAbMgNG8DmqWKMuE_mDmqu_zE5gM071x_YDY+Q+dA9WQ_8Mw@mail.gmail.com>
Date: Wed, 10 Jul 2019 16:15:31 +0200
In-Reply-To: <CAKCAbMgNG8DmqWKMuE_mDmqu_zE5gM071x_YDY+Q+dA9WQ_8Mw@mail.gmail.com>
	(Zack Weinberg's message of "Wed, 10 Jul 2019 09:06:53 -0400")
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* Zack Weinberg:

> Do we have a supported way to make dlinfo() queries for the shared
> library from which the call originates, without the library having to
> know its own soname?  (If it knows its own soname, it can call dlopen
> on itself, but I'm looking into a scenario where that information is
> not available.)

dladdr1 with RTLD_DL_LINKMAP returns the link map, which has a public
l_name member in <link.h>.  If you do not want to use the handle/link
map equivalence, you could dlopen l_name, and that should give you back
the same handle in an official way.

Thanks,
Florian