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| author | Denys Vlasenko <vda.linux@googlemail.com> | 2010-01-25 19:30:16 +0100 |
|---|---|---|
| committer | Denys Vlasenko <vda.linux@googlemail.com> | 2010-01-25 19:30:16 +0100 |
| commit | 24928ffd8d6eb7f410ea0a7b4530086cecfeea6e (patch) | |
| tree | fa0c4b0cdcebb2c4a9f8d5aefcd42fcafcbb89da /examples | |
| parent | 3581c625151d25d8e1cbc80c44337d398d97cf42 (diff) | |
| download | busybox-w32-24928ffd8d6eb7f410ea0a7b4530086cecfeea6e.tar.gz busybox-w32-24928ffd8d6eb7f410ea0a7b4530086cecfeea6e.tar.bz2 busybox-w32-24928ffd8d6eb7f410ea0a7b4530086cecfeea6e.zip | |
ntpd: explain why scripts can be run in quick succession
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Diffstat (limited to 'examples')
| -rwxr-xr-x | examples/var_service/ntpd/ntp.script | 20 |
1 files changed, 14 insertions, 6 deletions
diff --git a/examples/var_service/ntpd/ntp.script b/examples/var_service/ntpd/ntp.script index 90299ae8e..76c34bf74 100755 --- a/examples/var_service/ntpd/ntp.script +++ b/examples/var_service/ntpd/ntp.script | |||
| @@ -1,10 +1,12 @@ | |||
| 1 | #!/bin/sh | 1 | #!/bin/sh |
| 2 | 2 | ||
| 3 | exec 2>/dev/null | 3 | # Note that there is no provision to prevent several copies of the script |
| 4 | echo "`tail -n 99 "$0.log"`" >"$0.log" | 4 | # to be run in quick succession. In fact, it happens rather often |
| 5 | 5 | # if initial syncronization results in a step. | |
| 6 | exec >>"$0.log" | 6 | # You will see "step" and then "stratum" script runs, sometimes |
| 7 | exec 2>&1 | 7 | # as close as only 0.002 seconds apart. |
| 8 | # | ||
| 9 | # Script should be ready to deal with this. | ||
| 8 | 10 | ||
| 9 | dt=`date '+%Y-%m-%d %H:%M:%S'` | 11 | dt=`date '+%Y-%m-%d %H:%M:%S'` |
| 10 | 12 | ||
| @@ -13,17 +15,23 @@ if test x"$stratum" != x"" \ | |||
| 13 | && test 4 -ge "$stratum" \ | 15 | && test 4 -ge "$stratum" \ |
| 14 | && test 128 -le "$poll_interval" \ | 16 | && test 128 -le "$poll_interval" \ |
| 15 | ; then | 17 | ; then |
| 18 | echo "`tail -n 199 -- "$0.log" 2>/dev/null`" >"$0.log.$$" | ||
| 16 | echo "$dt: $1"\ | 19 | echo "$dt: $1"\ |
| 17 | "freq_drift_ppm=$freq_drift_ppm"\ | 20 | "freq_drift_ppm=$freq_drift_ppm"\ |
| 18 | "offset=$offset"\ | 21 | "offset=$offset"\ |
| 19 | "stratum=$stratum"\ | 22 | "stratum=$stratum"\ |
| 20 | "poll_interval=$poll_interval,"\ | 23 | "poll_interval=$poll_interval,"\ |
| 21 | "setting hardware clock" | 24 | "setting hardware clock"\ |
| 25 | >>"$0.log.$$" | ||
| 26 | mv -- "$0.log.$$" "$0.log" | ||
| 22 | exec hwclock --systohc | 27 | exec hwclock --systohc |
| 23 | fi | 28 | fi |
| 24 | 29 | ||
| 30 | echo "`tail -n 199 -- "$0.log" 2>/dev/null`" >"$0.log.$$" | ||
| 25 | echo "$dt: $1"\ | 31 | echo "$dt: $1"\ |
| 26 | "freq_drift_ppm=$freq_drift_ppm"\ | 32 | "freq_drift_ppm=$freq_drift_ppm"\ |
| 27 | "offset=$offset"\ | 33 | "offset=$offset"\ |
| 28 | "stratum=$stratum"\ | 34 | "stratum=$stratum"\ |
| 29 | "poll_interval=$poll_interval"\ | 35 | "poll_interval=$poll_interval"\ |
| 36 | >>"$0.log.$$" | ||
| 37 | mv -- "$0.log.$$" "$0.log" | ||