Avoiding Screen Pollution From Kernel Messages
By
default,
the
kernel
will
print
messages
to
the
console
device
(see
cons(3)).
This
can
be
problematic
when
also
running
rio
on
the
console,
as
is
common
on
terminals:
the
console
output
will
overwrite
the
existing
screen
contents.
To work around this problem, open a new terminal window and do:
cat /dev/kprint
This works because, according to the kprint discussion in cons(3), "if (the) console is a graphics screen, the data is sent either to the display or to kprint, but not both."
If you'd like a more permanent solution to the problem, make a directory '/sys/log/consoles' and put a line like
cat /dev/kprint >>/sys/log/consoles/$sysname >[2=1] &
somewhere in termrc or the included files (see cpurc(8)), or in your rio startup. On cpu servers, it may be useful to open a new window with something like:
{cat /dev/kmesg ; cat /dev/kprint} | tee /sys/log/consoles/$sysname
This will save a copy of the console output while also displaying it in a more controlled fashion.
It is probably not a good idea to redirect these to /dev/null; they may be important.