The operating system you port to might expect certain terminal key mappings that do not exist in the environment where you developed your application.
Alternatively, your code might rely on unique key mappings or operating-system-specific terminal control information stored in the user-interface environment files: the PROTERMCAP file on UNIX and the registry or a progress.ini file in Windows. For more information on environments, see OpenEdge Deployment: Managing ABL Applications.
Consider the following portability issues:
If you are planning to port your applications from one operating system to another, use the tilde (~) as an escape character in your application. While versions of OpenEdge running on UNIX interpret both the backslash (\) and the tilde as an escape character, versions of OpenEdge running in Windows interpret only the tilde as an escape character.
Wherever possible, use spaces rather than tabs. Spaces are consistent in size regardless of the operating system, but tabs might vary.
Use KEYFUNCTION in code logic, which is portable across platforms. Use KEYLABEL in messages to the user.
If you are planning to port your applications from one operating system to another, use the tilde (~) as an escape character in your application. While versions of OpenEdge running on UNIX interpret both the backslash (\) and the tilde as an escape character, versions of OpenEdge running in Windows interpret only the tilde as an escape character.