Linking without an Import Library

The figure below illustrates a simple case in which you create an application that uses a single dynamic-link library (.DLL) file.

┌──────────┐  ┌─────────┐    ┌─────────┐  ┌──────────┐
│ .OBJ and │  │.DEF file│    │.DEF file│  │ .OBJ and │
│.LIB files│  │(LIBRARY)│    │(imports)│  │.LIB files│
│          │  │(exports)│    │         │  │          │
└────┬─────┘  └────┬────┘    └────┬────┘  └─────┬────┘
     │             │              │             │
     └──────┬──────┘              └──────┬──────┘
            │                            │
                                        
       (1) LINK386                  (2) LINK386
                                        
            │                            │
       ┌────┴────┐                ┌──────┴──────┐
       │.DLL file│                │ .EXE file   │
       │(library)│                │(application)│
       └─────────┘                └─────────────┘

As depicted above, linking occurs in two steps:

• Object files (and standard libraries if any) are linked with a module definition (.DEF) file to create a .DLL file. A .DEF file is used that defines all functions exported by the .DLL file.

• Object files (and standard libraries, if any) are linked with a .DEF file to create an application (.EXE) file. A different .DEF file is used for this step; it defines all dynamic-link functions imported (used) by the application.