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+''' $Header
+''' 
+.de Sh
+.br
+.ne 5
+.PP
+\fB\\$1\fR
+.PP
+..
+.de Sp
+.if t .sp .5v
+.if n .sp
+..
+.de Ip
+.br
+.ie \\n.$>=3 .ne \\$3
+.el .ne 3
+.IP "\\$1" \\$2
+..
+'''
+'''     Set up \*(-- to give an unbreakable dash;
+'''     string Tr holds user defined translation string.
+'''     Bell System Logo is used as a dummy character.
+'''
+.tr \(bs-|\(bv\*(Tr
+.ie n \{\
+.ds -- \(bs-
+.if (\n(.H=4u)&(1m=24u) .ds -- \(bs\h'-12u'\(bs\h'-12u'-\" diablo 10 pitch
+.if (\n(.H=4u)&(1m=20u) .ds -- \(bs\h'-12u'\(bs\h'-8u'-\" diablo 12 pitch
+.ds L" ""
+.ds R" ""
+.ds L' '
+.ds R' '
+'br\}
+.el\{\
+.ds -- \(em\|
+.tr \*(Tr
+.ds L" ``
+.ds R" ''
+.ds L' `
+.ds R' '
+'br\}
+.TH TICKADJ 8 LOCAL
+.SH NAME
+tickadj - fiddle time\-related variables in the kernel
+.SH SYNOPSIS
+.B tickadj
+[
+.B -Aqs
+] [
+.B -a
+.I new_tickadj
+] [
+.B -t
+.I new_tick
+]
+.SH DESCRIPTION
+The
+.I tickadj
+program reads, and optionally modifies, several time\-keeping\-related
+variables in the running kernel, via
+.IR /dev/kmem .
+The particular variables it is concerned with are
+.IR tick ,
+which is the number of microseconds added to the system time during a
+clock interrupt,
+.IR tickadj ,
+which sets the slew rate and resolution used by the
+.IR adjtime (2)
+system call, and
+.IR dosynctodr ,
+which indicates to the kernels on some machines whether they should internally
+adjust the system clock to keep it in line with with time\-of\-day clock
+or not.
+.PP
+By default, with no arguments,
+.I tickadj
+reads the variables of interest in the kernel and prints them.  At the
+same time it determines an \*(L"optimal\*(R" value for the value of the
+.I tickadj
+variable if the intent is to run the
+.IR xntpd (8)
+Network Time Protocol daemon, and prints this as well.  Since the operation
+of
+.I tickadj
+when reading the kernel mimics the operation of similar parts of the
+.IR xntpd (8)
+program fairly closely, this is useful for doing debugging of problems
+with
+.IR xntpd (8).
+.PP
+Various flags may be specified to change the variables of interest in
+the running kernel.  The
+.B -a
+flag allows one to set the the variable
+.I tickadj
+to the value specified as an argument.  The
+.B -A
+flag will also cause
+.I tickadj
+to be modified, but instead will set it to the internally computed
+\*(L"optimal\*(R" value.  The
+.B -t
+flag may be used to reset the kernel's value of
+.IR tick ,
+a capability which is useful on machines with very broken clocks.  The
+.B -s
+flag tells the program to set the value of the variable
+.I dosynctodr
+to zero, a prerequisite for running the
+.IR xntpd (8)
+daemon under SunOS 4.0.  Normally
+.I tickadj
+is quite verbose about what it is doing.  The
+.B -q
+flag tells it to shut up about everything except errors.
+.PP
+Note that
+.I tickadj
+should be run with some caution when being used for the first time on
+different types of machines.  The operations which
+.I tickadj
+trys to perform are not guaranteed to work on all Unix machines.
+.SH FILES
+.nf
+/vmunix
+/unix
+/dev/kmem
+.fi
+.SH SEE ALSO
+xntpd(8)
+.SH HISTORY
+Written by Dennis Ferguson at the University of Toronto
+.SH BUGS
+Fiddling with kernel variables at run time as a part of ordinary
+operations is a hideous practice which is only necessary to make
+up for deficiencies in the implementation of
+.IR adjtime (8)
+in many kernels and/or brokenness of the system clock in some
+vendors' kernels.  It would be much better if the kernels were fixed
+and the
+.I tickadj
+program went away.