From Linux Man Pages
alevt-date - display/set time received via Teletext
alevt-date [options]
DESCRIPTION
alevt-date displays the time received from a Teletext source. It can be used to set the system time. The date
is not interpreted (not even transmitted on most channels). So it allows only adjustment of +/-12 hours. The
default allowed adjustment is limited to +/-2 hours (use -delta to change). Without the -set option it just dis-
plays the date in the format of the date(1) command.
OPTIONS
A summary of options is included below.
-set Set system time from time received via Teletext.
-delta seconds Maximum allowed adjustment made to the system time. The default is 7200 seconds (2 hours) and
the maximum that may be given is 12 hours.
-format string Format string to used to print the time. Look at strftime(3) for possible control sequences.
-vbi device Use the given device name (default: /dev/vbi).
-timeout seconds If the time can't be detected in seconds, the program is terminated with a SIGALRM.
--help Show summary of options.
--version Show version of program.
Before starting this program, you have to set the TV channel with another program like xawtv of set-tv.
Note: This program does not set the battery backed up clock of your computer. clock -w will do this.
FILES
/dev/vbi*
RELATED
alevt(1x), alevt-cap(1), strftime(3), date(1), clock(8).
BUGS
This program is just a toy. The time transmitted by the TV stations is more than inaccurate. Some are within a
few seconds of your local time reference but others are more then 15 minutes off. You've been warned. (And
don't assume the pkt8/30 time is better. It's even worse.)
No bug reports to <froese@gmx.de> *g*.
CATEGORY