In its initial concept, OpenVMS (then VAX/VMS) sought to provide the functionality and capabilities of a mainframe-class system at a small fraction of the size and cost, while at the same time providing higher levels of reliability and integrity. These goals were achieved by what has become OpenVMS' hallmark, an
emphasis on integrity and architectural leverage. Note: This is an entry to our OS Contest.
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Member since:2005-07-06
Member since:2006-07-18
VMS is still being actively developed. Version 8.2 has been out for a while, and Version 8.3 is coming out soon. Field test versions are already in customer's and hobbyist hands.
As for logical names, I feel that to attempt to embrace the entire capability at once is too much. Uses are many. As a simple example:
Disk drives on a system have a device name, whether it be C:, D:, DKA100: DKA200:, etc. However, usage of the device names is rather rigid. Using logical names for the disks is much better. DKA100: may be named DISK1, DKA200: may be named DISK2:, and so on. Your programs, data, and whatever may be on DKA100:, but referenced as on DISK1:. Ok, DKA100: is having problems, generating errors, going to die soon. By moving your programs, data, and whatever to possibly DKA300:, and re-defining the logical name DISK1: to have the value of DKA300, you can continue working without any other changes.
Another simple example:
You have an application that runs in background, and wakes up periodically to determine whether it needs to do any work. Lots of ways to do this, but with logical names, it's real easy and flexible. The application can use a library routine to evaluate the value of the logical name 'ReadyToGo'. If the value is 'True', or 'Yes', or whatever the application is looking for, then it can proceed, else not. There are multiple ways of setting the value of a logical name, manually or from within another program. A simple method for interprocess communication and/or control.
Now start to imagine the uses for being able to have a known 'token', the logical name, and the capability of assigning a value to the name and testing the value of the name.
When working on windoz the lack of logical names is one of my two biggest complaints.
Member since:2005-07-06
Member since:
2005-07-11
Thanks for the article, which I found very informative and interesting. I've been hearing about this OS for so many years, and yet have not really known an awful lot about its history or design philosophy until now.
I must say that I am thoroughly enjoying the "Alternative OS" series of articles.