On Saturday, 03/19/2011 at 02:24 EDT, "CHAPLIN, JAMES (CTR)" <james.chap...@associates.dhs.gov> wrote: > Yes I understand Alan is right on, and that vmcp protect's itself with a > limited buffer. But when I did the same command from the console instead > of using the vmcp command on the guest, it brought the entire server > down. VMCP limits the amount of output through buffers, how does VM > limit output from commands from the console? I should have phrased my > question that way.
Sorry I wasn't clear, James. When you enter "#CP some command" on the virtual machine console, two things have be true for CP to see it as a command: 1. CP has to be looking for "line editing" characters. That is, CP SET LINEDIT ON has to be in effect, AND 2. CP has to be looking for "#" as the end-of-line editing character. CP TERMINAL LINEND #. QUERY TERMINAL will tell you what the linend character is, and QUERY SET will tell you if CP even cares. Regardless, when output comes to the console, there is no buffering, even if it thousands of lines long. That's ok since the output doesn't go through the virtual machine OS, but directly from CP to the 3270. Only the 3270 PA1 key (the default "break" key) will stop the output. CP QUERY TERMINAL to look at the BRKKEY setting. Pressing the break key will cause CP to put up a CP READ, canceling any pending output. If #cp had in fact been caught by CP, not Linux, there would have been no buffering, no error message, and no server abend. Ergo, #cp was not caught by CP. Alan Altmark z/VM and Linux on System z Consultant IBM System Lab Services and Training ibm.com/systems/services/labservices office: 607.429.3323 mobile; 607.321.7556 alan_altm...@us.ibm.com IBM Endicott ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/
