.\" Copyright (C) 1993 by Andrew A. Chernov, Moscow, Russia.
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.Nd "adjusts the kernel time if the machine runs wall CMOS clock"
fixes kernel time (makes it UTC) using the current wall CMOS clock value,
the current time zone rule and the kernel timezone value. The adjustment is
exists, in other cases it is assumed that the machine runs UTC CMOS clock and
The adjustment is needed at boot stage and when a time zone
can be called in two forms:
(before any daemons are started).
makes the first adjustment and the initial time zone offset is stored into
This form is needed, when time zone changes occur.
uses the previously stored
time zone offset and the changed time zone rule to
produce the new time zone offset, fix the kernel time and store the new
It is recommended to use this form in root's
since this time matches most modern time zone changes.
This option is for diagnostic purposes. It causes
to print differences between the old and new time zone offsets
clears the kernel timezone structure and makes kernel always run at UTC
Super-user privilege is required for all operations.
Time zone change rule, see
.Bl -tag -width /etc/wall_cmos_clock -compact
Link to the current zone info file, see
.It Pa /etc/wall_cmos_clock
Presence of it indicates that the machine runs wall CMOS clock,
absence indicates UTC CMOS clock.
.It Pa /var/run/.adjkerntz
Text file with the stored current time zone offset in seconds.
No diagnostics, unless \-v option is specified.
If any error occurs, an error message printed to stderr and
exits with return code greater than zero.
Andrew A. Chernov <ache@astral.msk.su>
command appeared in FreeBSD 1.0.1