Edos
operating system for IBM mainframes
Edos is a discontinued operating system based upon IBM's mainframe DOS/360. The name stands for extended (or enhanced) disk operating system. It was later purchased by the West German computer company Nixdorf, who renamed it to NIDOS (Nixdorf Disk Operating System).
In 1970, IBM announced the IBM/370 product line along with new peripherals, software products, and operating systems, including DOS/VS that supplanted the DOS/360 line. Although IBM was rightly focused on their new products, the computing world was dominated by the IBM/360 line, which left a lot of users nervous about their investment.
Although there were a couple of projects emulating the IBM/370 on the IBM/360 (e.g., CFS, Inc.), other companies took a different approach, extending the then-current (and limited) DOS.
The Computer Software Company (TCSC) took the latter approach. Starting in 1972, they developed Edos, Extended Disk Operating System. They extended the number of fixed program space partitions from 3 to 6, added support for new hardware, and included features that IBM had offered separately. The first version of Edos was released in 1972, in response to the announcement by IBM that DOS Release 26 was the last DOS release to be supported on the System 360, and future DOS Releases would support System 370 machines only.
They also made available other third party enhancements such as a spooler and DOCS, from CFS, Inc.
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This entry incorporates text from “Edos” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.