### Subsystem Runtime Library DLLs

If you are shipping your application to other users, you can use one of three methods to make the IBM C and C++ Compilers subsystem library functions available to the users of your application:

- Statically bind every module to the library (.LIB) files.

  This method increases the size of your modules and also slows the performance because the DLL environment has to be initialized for each module.

- Use the DLLRNAME utility to rename the IBM C and C++ Compilers subsystem library DLLs. You can then ship the renamed DLLs with your application.
- Create your own runtime DLLs.

  This method provides one common DLL environment for your entire application. It also lets you apply changes to the runtime library without relinking your application, meaning that if the IBM C and C++ Compilers DLLs change, you need only rebuild your own DLL. In addition, you can tailor your runtime DLL to contain only those functions you use, including your own.

Create Your Own Subsystem Runtime Library
Create a Subsystem DLL