
ACTION (button) 

When a keyword is Boolean (T/F) and Write-Only, the interface
represents it as a pushbutton.  The only keywords of that kind
in our universe are KTL user commands. 

When you push the button, a KTL write will take place, sending
the appropriate instruction to the observing systems.  Typical
ACTION keywords are EXPOSE, PAUSE, and ABORTEX.

