In a message dated 5/5/2006 10:24:18 A.M. Central Daylight Time, [EMAIL PROTECTED] writes:
>I used to believe this was true, but it turns out it is not. A SEARCH >KEY CCW cannot execute in the domain of a LOCATE RECORD, so the chain is >not strictly ECKD. The description of multi-track SEARCH ID and SEARCH >KEY in the 2105 command manual clearly says that they stop at >End-of-Cylinder. Right. My error. ECKD will operate as I indicated on multi-track read operations and even on some write operations (e.g., Write CKD Next Track), but there is no way to include any kind of search loop within a Locate Record Domain. The Locate Record operands may define an ID to be searched for by the controller during the Locate Record positioning, but you cannot have your own search commands within a LRD. If a Define Extent or Prefix command begins a chain, then the chain becomes, in my unofficial terminology, ECKD-capable. The controller only enters the true ECKD mode (another unofficial private term) when a Locate Record or Locate Record Extended command is encountered. An ECKD-capable chain may go in and out of true ECKD mode any number of times. Bill Fairchild ---------------------------------------------------------------------- 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
