U_REDRAW

Clear screen and redraw it

WSupported on Windows

USupported on Unix

VSupported on OpenVMS

NSupported in Synergy .NET

xcall U_REDRAW

Discussion

U_REDRAW clears the screen and redraws it from scratch on the next update.

Normally, you don’t need to clear the screen and redraw it; as changes are made to the screen, the affected characters are repainted as needed.

The situations in which you would be most likely to use this subroutine are as follows:

• When you want to enable the user to redraw the screen with a key(s) other than Ctrl+R.
• When your application is returning from a task done in the shell. (Since the windowing system does not keep track of shell activities, the windowing environment must be redrawn upon re-entry.)
• When a portion of your application uses display statements to the terminal, and you subsequently return to the UI Toolkit portion of your code.