7.4.7.7 Using DLLs with GNAT

To use the services of a DLL, say API.dll, in your Ada application you must have:

Once you have all the above, to compile an Ada application that uses the services of API.dll and whose main subprogram is My_Ada_App, you simply issue the command

$ gnatmake my_ada_app -largs -lAPI

The argument -largs -lAPI at the end of the gnatmake command tells the GNAT linker to look for an import library. The linker will look for a library name in this specific order:

The first three are the GNU style import libraries. The third is the Microsoft style import libraries. The last two are the actual DLL names.

Note that if the Ada package spec for API.dll contains the following pragma

pragma Linker_Options ("-lAPI");

you do not have to add -largs -lAPI at the end of the gnatmake command.

If any one of the items above is missing you will have to create it yourself. The following sections explain how to do so using as an example a fictitious DLL called API.dll.