This is, I'm sure, a rare photograph of a tape containing an even rarer piece of software - a TOS system generated with multiprogramming capability. I generated it to mainly to see if it ran since I couldn't imagine it was possible. TOS was a tape resident variant of S/360 DOS (later to evolve into VSE). We had to maintain a current copy of TOS in the Datacenter although few people used it. I generated it partially using DOS because it was a lot faster and the supervisor generation macros were the same. Actually getting multiple programs running (up to 3) took forever. You'd start one, and then just a request to enter the console command to start another would cause the system residence tape to interrupt its mission and start searching for the code to issue a read to the operator console.