How do use dlopen ?

[mkhwang9]

I found 'dlopen' in Linuxis basically same as 'Loadlibrary' in MS Windows.

The function would be dynamically load a library during the program run, not necessary during startup. Now how do use this ? At link stage I got following message.

: undefined reference to 'dlopen_'

Please help!

[TimP]

As you haven't provided sufficient information, I'll ask you to make sure that your compiler is recent enough to include -ldl in the link options. If you have a mis-match between compiler version and linux distro, and don't want to upgrade, you could eliminate that problem by adding -ldl yourself.

[mkhwang9]

My compiler version 8.1, and I have used ldl option for ifort command.

The calling program has basically following lines:

pointer (addrFunc, subdll)

handle = dlopen (my_lib.so, RTLD_LAZY)

addrFunc = dlsym(handle, square)

call subdll(i, rvalue)

The shared library my_lib.so contains subroutine subdll. I wish I could see sample fortran source which use dlopen, and also build procedure. Actually the C sample source I encountered included dlfcn.h in it. I wonder if I would need similar thing in my Fortran source. Thank you for your attention.