Re: Symbol Hiding

Dear Paul,

THanks a lot for taking the time to reply.
I am sorry for multiple postings.

To examine the dynamic symbol table, use 'nm -D' or 'objdump -T'.
The sizeOfInt should not be in *that* output, and so is "invisible"
to the dynamic loader.

I tried doing what you told me but the outputs surprises me even
more .
Function hello is hidden in that out put too.

i did a objdump -T libhello.so , it dint show me any of the symbols
but hello should have been there.

so i did

objdump -t libhello.so, it shows the following:

000005e0 l F .text 00000000 __do_global_ctors_aux
00000000 l df *ABS* 00000000 libhello.c
0000056a l F .text 0000006c .hidden hello
0000179c l O .data 00000000 .hidden __dso_handle
0000054c l F .text 0000000a .hidden sizeOfInt
00000556 l F .text 0000000a .hidden sizeOfShort
00000545 l F .text 00000000 .hidden
__i686.get_pc_thunk.bx
00000560 l F .text 0000000a .hidden sizeOfLong

doesnt this mean even hello is hidden, but i exported it using the
macro.

Thanks

Newbei

On Mar 28, 9:58 pm, Paul Pluzhnikov <ppluzhnikov-...@xxxxxxxxxxx>
wrote:
"newbei" <newtoqto...@xxxxxxxxxxx> writes:
do nm libhello.so
I find both functions hello and sizeOfInt() in it why?

Because you are looking in the wrong place.

ELF shared objects (and executables) have *two* symbol tables --
a "regular" one (used mostly for debugging after the exe/DSO
is built) and a "dynamic" one (used by the dynamic loader for
inter-library symbol resolution).

To examine the dynamic symbol table, use 'nm -D' or 'objdump -T'.
The sizeOfInt should not be in *that* output, and so is "invisible"
to the dynamic loader.

Question 2:
What is the difference between strip and symbol hiding.

Strip manipulates the "regular" symbol table (which you do not care
about, except for debugging).

Cheers,
--
In order to understand recursion you must first understand recursion.
Remove /-nsp/ for email.


.

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