Another problem, even if you could get past the storage protect issues, would be the serialization of requests. QSAM was not designed expecting two or more different users to do a PUT to the same DCB at the same time. The data sent to the output file would very likely be overlaid if this happened, and whichever process gots its PUT serviced last would have its data more likely correct than the other processes.
Rob Scott gave one method of serialization by having only one server dequeueing and processing the "PUT" requests that were serialized via CS or CDS (ok, also CSG/CDSG) when being put on the to-be-processed queue. And the DEB is only one of many control blocks that are supposed to exist only within the same address space as that of the code that does the PUT. Others are the TIOT, buffer pool, IOBs, channel programs, etc. Bill Fairchild Software Developer Rocket Software 275 Grove Street * Newton, MA 02466-2272 * USA Tel: +1.617.614.4503 * Mobile: +1.508.341.1715 Email: [email protected] Web: www.rocketsoftware.com -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of [email protected] Sent: 20 April 2009 14:15 To: [email protected] Subject: DCB/DCBE In Common Storage Is this technique actually doable ? And if so what considerations are required ? If I copy the DCB/DCBE to a Getmained Area that is below the line and in a COMMON subpool, could a PUT request be issued from other programs in other address spaces ? (i.e. Not the Address Space that issued the GETMAIN AND OPEN) The address of the DCB/DCBE in COMMON Storage would be placed in a NAME TOKEN PAIR after the DCB was Opened. Other Programs in other Address Spaces could retrieve the Name Token Pair and subsequently the DCB address and issue a PUT Request. The thought being that all I/O from the satelite address spaces would be directed to a physical dataset residing in the Address Space that owns (opened) the DCB. There are other techniques that accomlish the same thing but thats not the issue here. I am specifically asking about issuing PUT requests for a DCB/DCBE in Common Storage. Has anyone ever tried to accomplish this. Paul D'Angelo ---------------------------------------------------------------------- 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
