[net.bugs.uucp] does FPE toggle Debug level?

chris@gargoyle.UChicago.UUCP (Chris Johnston) (08/10/84)

Pardon my ignorance.  On 4.2BSD, sending a floating point exception to
uucico is supposed to toggle between debug 0 and debug 30.  Does it work?
What should happen if uucico is running properly?  Under what circumstances
should nothing happen?  (After an hour I killed the sucker, although I
suspect it was just a very long file.)

trt@rti-sel.UUCP (08/12/84)

Uhm, it looks like vanilla 4.2BSD uucico does not toggle debugging
when it recieves SIGFPE.  Sorry!  It works in later versions.
On the other hand, it never was very useful.
If you are sure uucico is hung probably the best thing is to get a core
dump and run a debugger on the image to see what it was doing.
To get a core dump, try SIGIOT or SIGEMT.

To see if uucico is hung,
(a) if it is recieving a file see if a TM. file is growing.
(b) if it is sending a file, estimate the time needed and see if uucico
	has taken too long.
Also, an 'iostat 5' might help indicate uucico tty traffic.
	Tom Truscott

muller@sdccsu3.UUCP (Keith Muller) (08/12/84)

I have had a lot of success with (as root) sending a kill -STOP to the
runaway process, then using the 4.2 gcore program. This has the nice feature
of having a core image that you are sure was not altered by any signal 
handlers.

	Keith Muller
	UCSD Computer Center

bbanerje@sjuvax.UUCP (B. Banerjee) (08/16/84)

>> To see if uucico is hung,
>> (a) if it is recieving a file see if a TM. file is growing.
>> (b) if it is sending a file, estimate the time needed and see if uucico
>> 	has taken too long.
>> Also, an 'iostat 5' might help indicate uucico tty traffic.
>> 	Tom Truscott

The kludgy way I handled this on our (4.2) uucp was to redefine
DEBUG in uucp.h.  I just changed it to

#define DEBUG(l,f,s) if (Debug >= 1) fprintf(stderr, f, s); else \
	debugentry(1, f, s) <-- That first argument is a one.

debugentry was a routine I wrote that appended the stuff onto
a file called DEBUG in the uucp spool directory.  I then do a
"tail -f" of DEBUG whenever I want to monitor the progress of an
ongoing uucp transaction.  It can get slightly hairy when there
are more than one uucp transactions going simultaneously, but I
haven't had any real problems so far.

It isn't pretty, but it works.

Regards,
-- 
				Binayak Banerjee
		{allegra | astrovax | bpa | burdvax}!sjuvax!bbanerje
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