I am not a PowerBuilder expert. My impression is that PowerBuilder is used to develop GUI applications, both browser based and thick client apps.
My question is, can PowerBuilder also be used to develop a non-GUI application - a process that can then be scheduled to run unattended via a scheduler? An equivalent application type in the .NET world is a Console Application.
Sure you can. You can start coding in the application object's open event and you can use functions which are global in nature and for more object orientation you can use non-visual objects (NVOs) and datastores (datawindows without display properties) for data management and access. Everything is there for you to work on fantastic apps without anything to display to users in Windows. And if you need to receive commandline arguments look for the commandline parameter in the application object's open event.
If you are still unsure of what I indicated here, please ask and I can then try to clarify or answer in more detail.
The first object you need to implement in PowerBuilder is the application (i.e. the first object that will be loaded by the PB VM when it starts). It is a non-visual object (apart from the taskbar).
You can then open some windows from the open() event of the application or from any other methods, or you can only run into non-visual objects, that depends on what you want to perform. You won't necessary see a GUI window if you don't need to.
From the Windows / winapi point of view a PB application is a graphical application, not a console application. That is, you won't see a console window when you start it, nor you will be able to write something to stdout like a command line app out of the box. BTW, if you need to have a console, you can either hack the corresponding field of the compiled application PE header, or you can play with the console api to create one.
