As many are aware, z/OS Comm Svr FTP uses DISP=SHR + ISPF compatible ENQs when writing PDS members.
See for example this message for evidence: ======================= EZA2563W Data set dsname used exclusively by someone else. Explanation: A data transfer (get, put or append) of a partitioned data set (PDS) was requested and the member requested is currently in use. ==================== I am curious about how this actually works, specifically how/when FTP holds the exclusive *data set* ENQ (QNAME=SPFEDIT,RNAME=DSN). This would be the (hopefully short) ENQ that is held while actually doing I/O to the data set. What would happen if the FTP transfer started, this data set ENQ was obtained, and then the transfer hung for some period of time? Wouldn't that be bad? Or, perhaps FTP buffers the data for a PDS member write in memory until it has the complete member before doing I/O? Thanks, Kirk Wolf http://dovetail.com ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
