On Fri, 19 Feb 2016 10:45:24 +0000, Walter Marguccio wrote: > ... I use ftp to transfer a dataset from z/OS to a distributed maschine ? >The CP ? The SAP (the I/O processor) ?
Both. All of the code that you see (or could see if not for OCO) runs on a CP. The channel subsystem also has work to do. The exact workings of the OSA card are beyond my knowledge, but in general I/O is performed by creating a channel program and issuing START SUBCHANNEL. The channel subsystem then takes over and fetches the channel commands from memory, figures out what to do. For an output operatio, it then fetches the data from memory, transferring it to where it has to go. When the channel program is complete, it stores the results and generates an interrupt to signal the completion of the I/O. All of that work is done by the SAP. -- Tom Marchant ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
