[lttng-dev] dlopen, gcc -l and LD_PRELOAD

[Thibault, Daniel]

-----Message d'origine-----
Message: 6
Date: Wed, 20 Mar 2013 12:38:59 -0400

>    Meanwhile I've been playing with some very simple examples of .so use, and found that the behaviour of LD_PRELOAD is incompletely documented.  For instance, if I run:

Take a look at "man 8 ld.so". It should answer most of the questions you have about the dynamic linker libraries lookup mechanism.

>    The above should explain the trouble I've been having with lttng-ust's doc/examples/easy-ust and tests/demo.

Glad to see that you solved your issue!
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   That's what I meant by incompletely documented.  The ld.so man pages don't mention rpath/runpath in the description, do not explain the LD_PRELOAD caveats, do not mention the nodeflib executable tag, and don't detail how the ld.so.conf inclusions are sorted.  The online version (http://man7.org/linux/man-pages/man8/ld.so.8.html) is much better (though still lacking a bit) and certainly more up to date (February 2013 vs. Ubuntu's May 2007 version!).

Daniel U. Thibault
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