GKSGRAL is a full implementations of the ISO GKS standard. It is written in FORTRAN, and the application interface follows the final version of the FORTRAN binding [6]. The kernel is written to the level '2c', although versions on some systems (and some of the drivers) only support level '2b'. In particular, the version on IBM is only '2b'.
The main reason not to support '2c' is that Event Mode requires the operating and communications systems to support asynchronous interrupts. However, this feature is not required for Sample Mode. Thus, although it requires 'bending' the standard slightly, a pseudo Sample Mode is available on some devices which do not conform to level '2c' using the following procedure:
C Set string mode to sample
CALL GSSTM (WKID,1,1,0)
C Request the locator position
CALL GRQLC (WKID,1,STAT,TNR,PX,PY)
C Sample the character typed
CALL GSMST (WKID,1,1,NCH,STRING)
C Set string mode back to request
CALL GSSTM (WKID,1,0,1)
The current release of GKSGRAL-3D, Version 2.0, follows the final version of the ISO functional standard. It is also very close to the final FORTRAN binding apart from some minor differences which will be resolved at a future date.