User`s guide

Creating Windows
V+ communicates to windows through logical units, with logical unit numbers (LUNs) 20 to
23 reserved for window use. (Each task has access to its own set of four LUNs.) The basic
strategy for using a window (or any of the graphics instructions) is:
1. ATTACH to a logical unit
2. FOPEN a window on the logical unit
3. Perform the window's tasks (or graphics operations)
4. FCLOSE the window
5. FDELETE the window
6. DETACH from the logical unit
ATTACH Instruction
The ATTACH instruction sets up a communications path so a window can be written to and
read from. The syntax for the ATTACH instruction is:
ATTACH (glun, 4) "GRAPHICS"
glun variable that receives the number of the attached graphics logical unit.
(All menus and graphics commands that take place within a window will
also use glun.)
FOPEN Instruction
FOPEN creates a new window or reselects an existing window for input and output. When a
window is created, its name is placed in the list of available windows displayed when the
adept logo is clicked on. The simplified syntax for FOPEN is:
FOPEN (glun) "window_name /MAXSIZE width height"
glun The logical unit already ATTACHed to.
window_
name
The title that appears at the top of the window. Also used to close and
select the window.
width/height Specify the largest size the window can be opened to.
This instruction will give you a window with all the default attributes. See the description of
FOPEN and FSET in the V+ Language Reference Guide for details on how to control the
attributes of a window e6 for example, background color, size, and scrolling.
Creating Windows
(Undefined variable: Primary.Product_Name_V)Language User's Guide, version
17.x
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