how to force a dump?

[Christopher Lott]

In article <8904272154.AA00226 at era.ucar.edu.UCAR.EDU> era at NIWOT.UCAR.EDU writes:
>Question: is there some way, from one of the COS panels, to coerce
>OSx into dropping a core file?

Take this for what it's worth.  These are some very, _very_ old instructions
I once got from RTOC which were supposed to cause a pyramid machine (hung or 
otherwise) to panic.  Takes some diddling, and be warned that it *never*
worked for me.  If this is hopelessly obsolete and wrong, would someone
at Pyramid (hi, carl g?) please correct me?



                          How to Force a Panic


	     1.  If the system is hung, or you have a reason to cause a
	     crash go to COS frame B and halt it by pushing the Z-key.

	     2.  The system will  stop.   Make  a  note  of  the  Program
	     Counter  in  the  system  status  line  at the bottom of the
	     screen.  It will look like:
		                             FFxxxxxx

	     3.  Alter  memory  word location following that address.  If
	     pc = FF150808 then change location FF15080C.  (ie, add 0x4.)
	     Store  a  31000001 there.  This will be the next instruction
	     executed when the machine is restarted.   Type 'M' to modify 
	     memory - you will see a display something like this:
	     FF150800: 00000000 00000000 00000000 00000000
	      address  ^800     ^804     ^808     ^80C
	     The pyramid has long words (a 4 word boundary).

	     4.  Next, alter GR0.  Store the hex number 0000 0001 there.
	     This is General Register 0 -  displayed  in  frame B.  Use
	     command 'A' to modify registers.

	     5.  Restart the CPU  with  the  Z-key in frame B.
	     The  two new instructions force the computer to attempt exe-
	     cution of a word  instruction  on  a  byte  boundary.   This
	     forces  a  trap,  and if savecore enabled (in /etc/rc), core
	     will dump.  All the contents of memory will  be  written  to
	     the swap device.

	     6.  Hit <esc> 0, and watch to see that this happens.  If the
	     panic  was  caused  by a disk error, the core-write may fail
	     also.

	     7.  Reboot.  If savecore is enabled,  the  contents  of  the
	     swap device  will  be  copied  once again into the directory
	     specified; most usually, this is /usr/crash, but the  custo-
	     mers move it around.  There must be enough free space in the
	     file system to hold it.  It will be as large as  the  memory
	     copied,  and in the case of repeated failures there will al-
	     ready be other dumps stored there.

my note: attempted 870817 to no avail.

chris...
-=-
cml at cis.ohio-state.edu        Computer Science Dept, OSU          614-292-1826
 or:  ...!{att,pyramid,killer}!osu-cis!cml		<standard disclaimers>