K 10 svn:author V 3 imp K 8 svn:date V 27 2014-01-19T19:39:13.308686Z K 7 svn:log V 463 Introduce grab and ungrab upcalls. When the kernel desires to grab the console, it calls the grab functions. These functions should turn off the RX interrupts, and any others that interfere. This makes mountroot prompt work again. If there's more generalized need other than prompting, many of these routines should be expanded to do those new things. Should have been part of r260889, but waasn't due to command line typo. Reviewed by: bde (with reservations) END