CVS commit: src

[Matthias Drochner <drochner%netbsd.org@localhost>]

Module Name:    src
Committed By:   drochner
Date:           Mon Jan 18 10:50:24 UTC 1999

Modified Files:
        src/sys/arch/i386/isa: clock.c
Log Message:
Be more cautious about writing to the CMOS century byte. Update it only
if it contained a "19" before. There are machines (in particular PS/2
descendants) which have a checksum at this place.
Introduce a patchable kernel variable "rtc_update_century" to modify
the behaviour: 1="always update" (for testing and if one wants to set
the clock back) or -1="never touch".