________________________________ From: Charles Mills <[email protected]> To: [email protected] Sent: Sat, February 27, 2010 10:56:03 AM Subject: Re: Item on TPF
VSE does not support the Format-? (3? 5?) VTOC record that inventories free space. "Traditional" DASD space management in VSE involves a chart on the sysprog's wall showing which tracks of each volume are free. All "traditional" DASD space allocation in VSE is what z/OS JCL calls ABSTR (is that the right spelling?). A backstop against "oops" is that VSE datasets are usually defined with an expiration date (unlike z/OS) which causes VSE to complain if one attempts to overwrite them. The more modern approach in VSE uses large VSAM extents as "sub-regions" of a disk. VSAM then allocates space for sequential datasets within this area. I think there are also some third-party solutions. I know I set out to write one once (but did not complete the project). Charles Charles: Really?? how curious IBM did away with that a LONG time ago on MVS. My memory is bad on dates but I would guess in the late 80's (??). ANyone? Ed ---------------------------------------------------------------------- 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
