Different exported symbols in libc.a and libc.so

[Constantin Loizides <Constantin dot Loizides at isg dot de>]

Hello!

I am in the progress of writing an additional set of lib functions 
that override some of the exportet weak symbols of the
glibc. The idea is using the preload capabilities of ld
to first dynamically load my lib extension prior to the
libc.so, so that the application under question uses 
the overwritten functions of my lib extension.

So far so good, my lib extension crew in the last days until
I encountered the following problem:

It seems that for some reason (security?) some symbols are only
exported in the static version of the glibc.
Eg. chdir is the weak verson of __chdir, so I can define
my version of it, but __chdir is only exported in libc.a 
and not exported in the libc.so 

When looking in the compiler and linker scripts I could not
solve the problem to compile and link a shared version of
the glibs, which exports the (missing?) symbols.

Anyone any idea? Did I miss a fundamental
concept? Any hints and comments are highly welcome!

Cheers
Constantin

PS: Please cc me, as I am not subscribed on the list
(and sorry for the cross post, but I was unsure about
which list to use.)


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Constantin Loizides		        Phone:  +49 69 505030-212
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