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proposal: LD_PRELOAD for a specific library
- From: Sebastian Wick <sebastian at sebastianwick dot net>
- To: <binutils at sourceware dot org>
- Date: Tue, 11 Jun 2013 18:40:31 +0200
- Subject: proposal: LD_PRELOAD for a specific library
I'm working on a project where I want to change the behaviour of all
applications which use OpenGL (= which load libGL.so). To change the
bahaviour, I simply load my library first and overwrite dlopen, dlsym
and the target functions. If you set the LD_PRELOAD enviroment variable
on login, it may be changed so that the subprocesses don't load the
library anymore. If you change the config file for preloading
(/etc/ld.so.preload) my library gets loaded into every process, not only
the proccesses with OpenGL (applies the first method, too), which works
but is bad. The only option is the set LD_PRELOAD manually.
A new config file and or an enviroment variable which tells ld.so and
dlopen to load a library exactly before loading a target library. If the
target library is not loaded by the executable then no action should be
performed. The behaviour should be similar to LD_PRELOAD.
Furthermore dlsym must not return the address of the function of the
target library but the address of the function of the preloaded library,
if the symbol exists in the preloaded library.
I'd like to work on this but I want to hear your input first.