The shared library is in: libname='/afs/ipp-garching.mpg.de/home/o/osauter/bin/toks0/libinterposgfortran_idl.so' for the toks0x machines It will be in libname='/afs/ipp-garching.mpg.de/home/o/osauter/bin/sxaug/libinterposgfortran_idl.so' when I manage to compile without getting an "ELF class problem in idl" (problem 32/64 bit libraries) To make this shared library, execute: make interposgfortran_idl In the folder: ../interpos_libs (after svn co ....) cf http://spc.epfl.ch/interpos to execute in idl the test or re-execute: .full_reset_session .rnew test_idl_interpos_all_cases aa=test_idl_interpos_all_cases(1) to execute a loop through all test cases: aa=test_auto_series()