Description:
This performs a
synchronisation handshake with the user interface. This is required if the current task has been
outputting messages via the user interface and now wants to use a graphics cursor on the command
device. If a synchronisation error occurs, then an error report is made and the status value is returned
set to MSG__SYNER.
Invocation
CALL MSG_SYNC( STATUS )
Arguments
STATUS = INTEGER
(Given and Returned)
The global status: it is returned set to MSG__SYNER on error.