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Reasons for Porting

There are several reasons for porting VICAR to Unix. The most important reason is that Unix is an industry standard operating system, unlike VMS. A wide variety of computer vendors support Unix. Although each vendor's flavor of Unix is slightly different, they are fundamentally similar. The available hardware for Unix systems is typically much faster and cheaper than VAX hardware. So, the port removes the reliance of VICAR on one computer vendor, and allows for a wide range of options. Not only is the computer itself cheaper, the various peripherals and display devices are often cheaper as well.

Another reason for performing the port is that many scientists and experimenters are moving towards Unix workstations at their facilities. In order for them to use VICAR at their sites, it must run on their systems.

The Posix standard for operating systems closely mirrors many of the Unix system calls. Porting VICAR to Unix makes it possible to run on the Posix standard eventually. While VMS will also be Posix-compliant in the future, the system calls to do so will be the Unix-style system calls.

Finally, porting VICAR to Unix allows an opportunity to clean up and modernize the VICAR system. While most of the applications will be ported straight over (without any significant new features), the executive and system-level VICAR code has been significantly updated. Performing the port will ease the transition into a more modern, window-oriented user interface.