Universal Time-Sharing System

The Universal Time-Sharing System (UTS) is a discontinued <a href="/facts/Operating_system/8XTuvMh2">operating system</a> for the <a href="/facts/Scientific_Data_Systems/E6m5jUpC">XDS</a> <a href="/facts/SDS_Sigma_series/56e0aEVA">Sigma series</a> of computers, succeeding Batch Processing Monitor (BPM)/Batch Time-Sharing Monitor (BTM). UTS was announced in 1966, but because of delays did not actually ship until 1971. It was designed to provide multi-programming services for online (interactive) user programs in addition to batch-mode production jobs, symbiont (<a href="/facts/Spooling/fPbanPPu">spooled</a>) I/O, and critical real-time processes. System <a href="/facts/Daemon_(computing)/bzuEVGGX">daemons</a>, called "ghost jobs" were used to run monitor code in user space. The final release, D00, shipped in January, 1973. It was succeeded by the CP-V operating system, which combined UTS with features of the heavily batch-oriented <a href="/facts/Xerox_Operating_System/TPbxvkcV">Xerox Operating System</a> (XOS).

Universal Time-Sharing System open-in-new

Universal Time-Sharing System