BOS/360

History of IBM mainframe operating systems

BOS/360 (Basic Operating System/360) was an early IBM System/360 operating system.

Origin

BOS was one of four System/360 Operating System versions developed by the IBM General Products Division (GPD) in Endicott, New York to fill a gap at the low end of the System/360 line when it became apparent that OS/360 was not able to run on the smallest systems. BPS (Basic Programming support) was designed to run on systems with a minimum of 8,192 bytes of memory and no disk. BOS was intended for disk systems with at least 8,192 bytes and one 2311 disk drive. DOS and TOS were developed for systems with at least 16,384 bytes and either disks or tape drives.

BOS was released in October 1965, nearly two years before OS/360,[1] thus BOS was the only disk based operating system available at launch for a machine that was marketed as disk based.

Components

BOS consisted of the following components:

IBM 1070 Process Communication Supervisor

The IBM 1070 Process Communication Supervisor was a dedicated process control system that ran as an extension under BOS.

Relying on the BOS supervisor to handle ordinary physical and logical I/O operations (i. e., for cards, disk, etc.), the PC supervisor is specialized to the process control aspects of the user's program.[2]

References

  1. Pugh, Emerson, et al. "IBM's 360 and Early 370 Systems". MIT Press, 1991,p.331
  2. IBM Corporation (1965). IBM System/360 Basic Programming Support and Basic Operating System/360 Programming Systems Summary (C24-3420-0).

Further reading

This article is based on material taken from the Free On-line Dictionary of Computing prior to 1 November 2008 and incorporated under the "relicensing" terms of the GFDL, version 1.3 or later.