error while loading shared libraries

Question

I have a project organized as

\bin\cmain
\lib\libxmlrpc_client++.a
\lib\libxmlrpc_client++.so.4
\lib\libxmlrpc_client++.so.4.16

My c program cmain need to dynamically link clib.so.4. While I compile the code, I use -L.../lib to indicate directory lib and use -lxmlrpc_client++. However, my code get error while loading shared libraries:

libxmlrpc_client++.so.4: cannot open shared object file: No such file or directory

Any ideas to fix this?

PS: Problem solved, a good reference to the problem: http://gcc.gnu.org/ml/gcc-help/2005-12/msg00017.html

Answer 1

You need to tell the dynamic linker where to look for the libraries. Assuming this is some sort of UNIX/Linux system, this can be done either via setting the LD_LIBRARY_PATH environment variable before executing the program:

export LD_LIBRARY_PATH=/path/to/lib
./run-my-program

or by setting the run-time linker path during compile time:

gcc -L/path/to/lib -Wl,-rpath,/path/to/lib -lxmlrpc_client++ ...
./run-my-program

Both approaches have problems. Google for "why LD_LIBRARY_PATH is bad". The command-line options for setting the run-time linker path varies from one compiler to another.