[mythtv-users] can't get wakealarm to write to BIOS

[Mike Hodson]

On Fri, Dec 8, 2017 at 7:13 PM, Bill Meek <keemllib at gmail.com> wrote:

> On 12/08/2017 12:53 PM, Marius Schrecker wrote:
>
>> $sudo bash -c "echo `date '+%s' -d '+ 6 minutes'` >
>> /sys/class/rtc/rtc0/wakealarm
>
>

> Use: echo `date '+%s' -d '+ 6 minutes'`| sudo tee
> /sys/class/rtc/rtc0/wakealarm"


Bill, normally sudo of echo redirecting will not work; the user-shell is
still used for redirection.
However, in his case, not only is he running bash -c "full command with
redirect", but he also later cats the result
in /sys/class/rtc/rtc0/wakealarm and comes up with the proper time/date.

>>
>> $date
>> fr. 08. des. 19:42:53 +0100 2017
>> $sudo bash -c "echo `date '+%s' -d '+ 6 minutes'` >
/sys/class/rtc/rtc0/wakealarm"
>> $ cat /sys/class/rtc/rtc0/wakealarm
>> 1512758974
>> $ date -d @1512758974
>> fr. 08. des. 19:49:34 +0100 2017
>>

I've even performed an empirical test, and indeed as long as the redirect
is within the double-quotes of bash -c "command here > file" it works for
me in a different scenario:

mike at bifrost /root $ sudo bash -c "echo `date '+%s' -d '+ 6 minutes'` >
derp"
Password:
mike at bifrost /root $ ls -al derp
-rw-r--r-- 1 root root 11 Dec  9 01:21 derp
mike at bifrost /root $ cat derp
1512800877

Thus I have to believe that Marius's shell is indeed writing the exposed
rtc device properly, unless there are some syntax quoting issues somewhere
else..

I'm puzzled here, and am curious if A:  it has ever worked at all properly,
and if not, B: if the BIOS is buggy?

Mike
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