Wrong results from dynamic libraries

Hello all,

I am having problems with shared libraries.

mstrdev@scar:/OS_CHANGES/OS_CHANGES/DIMESERVER/gsoap_2_7/gsoap-2.7.9e/samples/calc_src> ldd test_shift
libtestlib.so => /home/mstrdev/MSTRPROJ/code_development/external/lib/libtestlib.so (0x00007fd4c977f000)



test_shift.cpp
---------------

Code:

main()
{

s = Function_A(1, 2, 3)

printf("RETURN VALUE IS %d", s);

}

libtestlib.so
------------

Code:

int Function_A (int input1, int input2, int input3)
{
return 1;

}

The problem is that "return 1" comes back as -603456842

Why?

Is this some kind of strange property with dynamic libraries?
How can one find out what is going on?

TIA

Shared Libraries

Have you set say LD_LIBRARY_PATH?

There is also LD_DEBUG to help trace problems (see link)

How did you create your shared library (gcc -shared)

Does your program have a prototype for Function_A() in scope?

Originally Posted by d0mufasa

Hello all,

I am having problems with shared libraries.

mstrdev@scar:/OS_CHANGES/OS_CHANGES/DIMESERVER/gsoap_2_7/gsoap-2.7.9e/samples/calc_src> ldd test_shift
libtestlib.so => /home/mstrdev/MSTRPROJ/code_development/external/lib/libtestlib.so (0x00007fd4c977f000)



test_shift.cpp
---------------

Code:

main()
{

s = Function_A(1, 2, 3)

printf("RETURN VALUE IS %d", s);

}

libtestlib.so
------------

Code:

int Function_A (int input1, int input2, int input3)
{
return 1;

}

The problem is that "return 1" comes back as -603456842

Why?

Is this some kind of strange property with dynamic libraries?
How can one find out what is going on?

TIA

your code has nothing to do with a library. You just wrote some function, and then called it in main. Is "function_A" from the lib? Have you declared 's' to be the return type?

Duplicate threads merged.

Hello,

Don't know what is going on here.

I had changed the programming so that I could pass a value in and that it would hopefully get assigned the correct data.

I changed it as follows:

Code:

main ()
{
int returncode;

[snip]

retval = TransHist_Create( merchant_id, &trans_hist_id, transact_id, from_step_id, num_proc, num_succ, num_fail, num_user_err, todays_date, proc_user_id, addendum, getlocalhost(), getpid(), 0, __FILE__, __LINE__, &returncode);

}

Code:

Now, in the function : TransHist_Create(...., *returncode)
{
....... [snip] ...

*returncode = 0;
return 0;
}

BUT ..

in main, the returncode is set to --> 1 <-- ?!?!

Why??

I do not understand how return codes can be returned to the caller INCORRECTLY when they are implicitly set to a value in the function.

The function is in a static library. I got rid of the references to dynamic libraries because of the problems.

Has anyone seen anything like this? Is it memory corruption or something? How can I find out what is going on?

TIA