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Clear tagged and/or modified attributes in a screen

This function clears the tagged and/or modified attributes for all items in a screen. While it might be useful in some normal full-screen applications, it is probably most useful in applications that receive output from a non-full-screen source but populate a screen from that source, in order to be able to use legacy full-screen code.

When the legacy code has produced an updated version of the screen, the code communicating with the external source should probably clear the tagged and/or modified bits, just as a Read Screen statement would.

Under Model 204 7.8 and later, $Screen_clear is callable.


[%one =] $Screen_clear(scr_item, [mod|tag])

Syntax terms

%one This function always returns 1.
scr_item The screen item in the screen for which attributes are to be cleared. This can be a variable of the form %screen:item or a screen item name variable of the form :%string.
mod or tag A string indicating the attributes to be cleared. The string for mod clears only the modified attributes, and the string for tag clears only the tagged attributes. If any other value is specified, including no value, both modified and tagged attributes are cleared.


This code fragment clears the modified attribute for screen foo (which contains screen item bar):

%rc = $screen_clear(%foo:bar, "MOD")