stuck xterm

[Edward Vielmetti]

ultrix 4.0, decstation 5000.  decwindows window manager, and an xterm
window the entire height of the screen and 1/2 the screen wide.

the xterm was started from a decterm window (xterm &).

when I cat a long file (50K) to that window, the scrolling is choppy,
but no more that I would expect.  but: when I cat that same file through
a simple perl filter (i.e. slightly slower display) the xterm scrolling
sometimes gets stuck.  The window freezes.  Control-left doesn't
bring up a menu, ps shows "idle", everything is gone.  Somewhere like
a minute or two later (after I hit some buttons) the window comes
back and all is well again.

I've had it happen with two different xterms, using exactly the same
test.  Not sure how many times it's happened before or whether I could
repeat it tomorrow.

Is there any way to get a trace of what's happening in a currently running
Ultrix process (like the AT&T "truss" or the SunOS "trace" ?)  Sure
would be nice right now.

--Ed

Edward Vielmetti, U of Michigan math dept <emv at math.lsa.umich.edu>
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