Import libraries are created by IMPLIB and are used to link DLLs with applications.

Import libraries are somewhat similar to standard libraries:

• You specify import libraries and standard libraries in the same command-line field of LINK386.

• Both types of libraries resolve external references at link time.

However, import libraries differ from standard libraries in that they contain no executable code. Rather, they identify the DLLs where the executable code can be found at run time.

Creating import libraries is an extra step. Nevertheless, import libraries are recommended for use with all DLLs for two reasons:

• IMPLIB automates much of the program creation process for you. To use IMPLIB, you need to supply the .DEF file you already created for the dynamic link library. Without an import library, you must create a second .DEF file that explicitly defines all needed functions in the dynamic link library.

• Import libraries make it easier for one person to write a library and another to write the application. Much of the linking process (linking the .DLL file and creating the import library) can be done by the author of the dynamic link library. The import library and associated .DLL file can then be given as a unit to the person linking the application--that person need not worry about creating a .DEF file.