Subject: should cngetc block?
To: None <>
From: None <>
List: tech-kern
Date: 02/05/2002 13:33:21

I'm looking for a function like cngetc (in dev/cons.c), but
doesn't block for an available char.

Looking at cngetsn, the call to cngetc is bracketed by
cnpollc, to apparently turn on and off polling.  So it seems
to me that that cngetc should not block, by default, but
will only block if enabled by cnpollc(1).

Which brings us to com_common_getc (called by cngetc) in

com_common_getc blocks for char, and comcnpollc (called by
cnpollc) is empty.

So my question is this: should com_common_getc not block by
default (returns -1 if no char available), and will only
block if enabled by a call to comcnpollc(dev,1)?

Thanks for your time!