character loss in l_input line discipline

[David Beckemeyer]

I have a terminal driver for SCO Xenix.   Under heavy input
loading (multiple ports conitinuous 960+ cps) occasionally
characters are lost.

I have traced it to the point where the charcaters have made it
all the way to the receiver interrupt routine, which has filled the
ccblock and then calls the kernel "l_input" routine.   Occasionally
the characters never get to the application after getting passed
to "l_input".

Where are they going?   Under what circumstances will "l_input"
dump the characters to the bit bucket?  Out of clists perhaps?
What can I do about it in the driver?  I have tried "throttling"
the receiver interrupt to never pass more than a certain number
of characters per interrupt, and it didn't seem to matter.
-- 
David Beckemeyer			| "To understand ranch lingo all yuh
Beckemeyer Development Tools		| have to do is to know in advance what
478 Santa Clara Ave, Oakland, CA 94610	| the other feller means an' then pay
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