Restartability

GS/OS supports the concept of program “restartability”. This allows programs which are written in a certain way to remain in memory in a purgeable state so that if they are invoked again, and their memory has not been purged, they can be restarted without any disk access. This greatly increases the speed with which restartable programs can be executed.

The ORCA environment specifies whether or not a program is restartable via a flag character in the SYSCMND file. The GS/OS standard method, however, is to set the appropriate flags bit in the GS/OS Quit call. This is the method that GNO/ME supports. Provided with the GNO/ME standard library is a routine rexit(3). rexit(3) only works with ORCA/C 2.0. rexit(3) works just like the normal C exit(3) call but it sets the restart flag when calling QuitGS.

The standard ORCA/C 1.3 libraries are not restartable, but the ORCA/C 2.0 libraries are.