> Overlays were much more important before the availability of virtual storage than after.
Right-o. Overlays are in effect programmer-managed virtual storage. Charles -----Original Message----- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On Behalf Of john gilmore Sent: Tuesday, February 20, 2007 6:27 PM To: IBM-MAIN@BAMA.UA.EDU Subject: Re: IBM System/360 Operating Systems history > > I don't recall if TOS supported overlay structures. That is not an idea > whose time has come: loading overlay segments from tape. > Not when DASD or crypto-DASD is available; but both IBSYS and TOS supported overlay segments loaded from tape. (Overlays were much more important before the availability of virtual storage than after.) ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html