This vintage IBM 7090/7094 IBSYS Operating System Version 13 Input/Output Control System dated 1965 is a rare find for collectors and computing enthusiasts.  This manual will enable you to learn more about the system and how it worked.  It will be a valuable addition to any collection. File No. 7090-30, Form C28-6345-4.  There is a fold-out of Figure 3.  Format of the File Control Block on page 77 and 78.

It is in nice condition considering age (no writing, no damage to any of its 98 pages, except small tear front page above staple).  See photos for examples that include black and white photos, flowcharts, and diagrams.  Pages are whiter than shown in some photos.  Ships media U.S. Only.  No International.

S&H consists of packaging, invoice, time and travel plus actual cost when applicable.  Smoke-free.  See other IBM items listed.  I will answer all questions when possible.  Thank you for looking. Will combine shipping on multiple purchases. Just let me know before you pay so I can adjust invoice.