Basic Operating System/360 (BOS/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 KB of main storage and no disk. BOS was intended for disk systems with at least 8 KB and one 2311 disk drive. DOS and TOS were developed from BOS for systems with at least 16 KB and either disks (DOS) or tape drives only (TOS). BOS was released in October 1965, nearly two years before OS/360, 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."