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Diffstat (limited to 'sys-utils/hwclock.8.adoc')
| -rw-r--r-- | sys-utils/hwclock.8.adoc | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/sys-utils/hwclock.8.adoc b/sys-utils/hwclock.8.adoc index 3e181ed..0b23a37 100644 --- a/sys-utils/hwclock.8.adoc +++ b/sys-utils/hwclock.8.adoc @@ -101,6 +101,11 @@ The first two are only available on the first call of *settimeofday*(2) after bo *-w*, *--systohc*:: Set the Hardware Clock from the System Clock, and update the timestamps in _{ADJTIME_PATH}_. With the *--update-drift* option also (re)calculate the drift factor. Try it without the option if *--systohc* fails. See *--update-drift* below. +*--vl-read*, *--vl-clear*:: +Some RTC devices are able to monitor the voltage of the backup battery and thus provide a way for the user to know that the battery should be replaced. The *--vl-read* function retrieves the Voltage Low information and decodes the result into human-readable form. The *--vl-clear* function resets the Voltage Low information, which is necessary for some RTC devices after a battery replacement. ++ +See the Kernel's _include/uapi/linux/rtc.h_ for details on which pieces of information may be returned. Note that not all RTC devices have this monitoring capability, nor do all drivers necessarily support reading the information. + include::man-common/help-version.adoc[] == OPTIONS |