I've been wading thru the documentation (DFSMS Using Data Sets), etc... trying to figure out why the DCBBLKSI field of my DCB is not being filled in for a RECFM=U data set for INPUT. (Non-LBI)
In particular, I want to allocate a buffer of sufficient size to hold any block
we might read for a pre-existing RECFM=U data set. I put zeros into the DCB before the OPEN; then I do the OPEN... expecting the DCB to have the DCBBLKSI field set to the block size... But - it remains zero. The JCL (well, an SVC 99 actually) doesn't specify a BLKSIZE for the file. But - the file is catalogued, I would have expected the DCBBLKSI field to get the BLOCK SIZE from the catalog? Does anyone know why the DCBBLKSI field would not be filled in ? The example code for determining the # of bytes read (from IBM's doc) determines the blksize after the READ (+CHECK) macros are issued. Is it possible that the blksize for a RECFM=U cannot be determined at OPEN time, but only after a READ? - Thanks - - Dave Rivers - -- riv...@dignus.com Work: (919) 676-0847 Get your mainframe programming tools at http://www.dignus.com ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
