PRO/5 Terminal Window

Because PRO/5 traditionally runs in a character-based environment, it is also a sophisticated terminal emulator. In the past, previous BASIS products have offered support for the X Windows System on some platforms. On an X terminal, as well as in other graphical environments, the size of the terminal (actually the window) can change at any time. This is usually not of interest to the application. If it is, the physical dimensions of the terminal are updated dynamically, as provided in FIN(0), bytes (3,1) and (4,1), and may be retrieved at any time. (Application developers need not worry unduly about the size of the terminal window changing, because Visual PRO/5's internal data structures are not affected. At startup, Visual PRO/5 creates a virtual terminal with 80 columns and 25 rows, regardless of the physical display's dimensions.)

A special ALIAS line in the config.bbx file serves to supply the device alias for the PRO/5 terminal window. A typical name might be T0. The installation procedure takes care of adding at least one such line, and it looks something like this:

ALIAS T0 SYSWINDOW

The pseudo-device SYSWINDOW tells Visual PRO/5 that this is the device alias to associate with the terminal window. You may use any valid alias name, if your application requires a specific name or type of name. One ALIAS entry must be present in config.bbx for each device alias used, and Visual PRO/5 will not run without at least one valid alias for SYSWINDOW.

Multiple SYSWINDOW Devices

You can open as many SYSWINDOWs as you like. For example, you could run Visual PRO/5 from T0, then open T1 on channel 1, provided that T0 and T1 are both SYSWINDOW aliases. (Note: If another Visual PRO/5 task on the same workstation then opens T1, it will be using a different window. The only thing the windows would share are any modes from the alias line and the value returned by FID(0).)

All SYSWINDOWs are drawn using the current color map, and any changes to the color map are reflected in all SYSWINDOWs immediately. However, the Font and Size dialog affects the only system console. The font and size attributes of non-console SYSWINDOW devices may be set using device modes and mnemonics, discussed later in this section.