Usually, the best approach to migration is to begin with the main executable files, then, one at a time, migrate each application DLL.
You can test the full function of the project after each migrated piece. You cannot use this method for projects that use IBM Open Class Libraries (IOC) across DLL boundaries.
If you have projects that use IOC libraries across DLL boundaries, you must convert and test each application DLL separately.
If you built your application with VisualAge C++ for OS/2 Version 3.0 or VisualAge for C++ for Windows Version 3.5, you must convert your EXEs and DLLs to use the new C/C++ run time. There is static data stored in the run times, such as environment data, and exception and new handlers that are used by the code in the DLL. You do not have to rebuild these DLLs (you may not have the source).
We have provided a set of C/C++ run time migration DLLs. They provide all the entry points that were present in VisualAge C++ for OS/2 Version 3.0, VisualAge for C++ for Windows Version 3.5, they maintain the pre-ANSI atexit() processing behaviour.
To convert a DLL (appl.dll, for example) to the C/C++ migration DLLs, the following commands are required: