DSOM programs and class libraries are compiled and linked like any other SOM program or library. The header file "somd.h" (or for C++, "somd.xh") should be included in any source program that uses DSOM services. DSOM run-time calls can be resolved by linking with the SOMobjects Toolkit library: "libsomtk.a" on AIX and "somtk.lib" on OS/2 or Windows. (The DSOM DLL(s) - "somd.dll", for AIX or OS/2, or "somd1.dll" and "somd1.dll" for Windows - will be loaded at run time.) For more information, see "Compiling and linking" in Chapter 3, "Using SOM classes in Client Programs," and the same topic in Chapter 5, "Implementing Classes in SOM."