PC-Hypertext: Attributes 3.

- PC-Hypertext can be configured to contain calls to DOS programs
external to the authored application.  When a system user
activates a "program call", the PC-Hypertext program stores the
information necessary to describe the current user location in
the authored application, and then temporarily exits from memory.
The system memory is then allocated in support of the external
(called) program.  When user interaction with the external
program is terminated, PC-Hypertext is automatically reloaded to
the system and the user is returned to the last active display
prior to the implementation of the external program call.

<dfile81>   PC-Hypertext: Attributes 1.