source: MondoRescue/branches/3.3/mindi-busybox/examples/var_service/ntpd/ntp.script@ 3803

#!/bin/sh

# Note that there is no provision to prevent several copies of the script
# to be run in quick succession. In fact, it happens rather often
# if initial syncronization results in a step.
# You will see "step" and then "stratum" script runs, sometimes
# as close as only 0.002 seconds apart.
#
# Script should be ready to deal with this.

dt=`date '+%Y-%m-%d %H:%M:%S'`

echo "`tail -n 199 -- "$0.log" 2>/dev/null`" >"$0.log.$$"

if test x"$1" = x"unsync" \
; then
    # No replies for our NTP requests were seen for some time.
    #
    # Among more mundate cases like network outages, this happens
    # if we ran for a LONG time (days) and ntp server's IP has changed.
    # ntpd has no code to re-resolve peers' addresses to IPs,
    # we need to help it:
    #
    echo "$dt: $1"\
        "syncronization lost, restarting ntpd"\
        >>"$0.log.$$"
    mv -- "$0.log.$$" "$0.log"
    kill $PPID
    exit
fi

if test x"$stratum" != x"" \
&& test x"$poll_interval" != x"" \
&& test 4 -ge "$stratum" \
&& test 128 -le "$poll_interval" \
; then
    echo "$dt: $1"\
        "freq_drift_ppm=$freq_drift_ppm"\
        "offset=$offset"\
        "stratum=$stratum"\
        "poll_interval=$poll_interval,"\
        "setting hardware clock"\
        >>"$0.log.$$"
    mv -- "$0.log.$$" "$0.log"
    exec hwclock --systohc
fi

echo "$dt: $1"\
    "freq_drift_ppm=$freq_drift_ppm"\
    "offset=$offset"\
    "stratum=$stratum"\
    "poll_interval=$poll_interval"\
    >>"$0.log.$$"
mv -- "$0.log.$$" "$0.log"