Re: linking at run time problem

[Greg Chicares]

On 2007-05-01 22:56Z, g-h-d wrote:
> 
> g++ -L/usr/local/lib -o"testing_hal"  ./main.o   /main.o: In function
> `hal::set_err_fn(char const*, char const*, int, int)':
> /usr/local/include/hal/err_hnd.h:257: undefined reference to `hal::err_hnd'

That suggests that a required library wasn't linked.

> g++ -L/usr/local/lib -o"testing_hal"  ./main.o   -lhal_base
> Finished building target: testing_hal
>  Build complete for project testing_hal

Linking to the library fixes the link-time problem.

> Runtime error:
> /Debug/testing_hal: error while loading shared libraries: libhal_base.so.0:
> cannot open shared object file: No such file or directory
> 
> Attempt #2 compiles but not #1, so i deduce that adding -lhal_base is
> probably a good idea, but i still have a runtime error. The incriminated
> file libhal_base.so.0 does reside in the specified library specified by -L
> i.e. /usr/local/lib.

The '-L' linker switch tells the linker (but not the
operating system) where to find that library. How you
tell the OS where to find it is OS specific; it's not
a 'make' problem.