Open an AGI device and return an identifier to the current picture. If there are no pictures on the device then a base picture is created and made current. If the size of the display window has changed since a previous database operation the database is cleared and a message sent to the user. The access mode does not affect the database operation, but it is used by the graphics system to determine if the display should be cleared the first time a zone is created; ’READ’ and ’UPDATE’ access do not clear the display, but ’WRITE’ access does.

CALL AGI_OPEN( WKNAME, ACMODE, PICID, STATUS )

WKNAME = CHARACTER $\ast$ ( $\ast$ ) (Given)

ACMODE = CHARACTER $\ast$ ( $\ast$ ) (Given)

PICID = INTEGER (Returned)

STATUS = INTEGER (Given and Returned)