Need some help with exec and CAT

Setup, Configuration and Use Beginners
1

Hi,

I need some help to read my energy meter

I have following thing

Thing exec:command:zaehler [command="cat /dev/ttyUSB0 | xxd  -l204 >z1.txt", interval=15, timeout=5, autorun=false]

The energy meter is on the USB 0. If I use the same command on the console the file z1.txt will be stroaged.

On openhab I get an error

2018-11-29 21:58:41.167 [INFO ] [el.core.internal.ModelRepositoryImpl] - Refreshing model 'zaehler.things'

==> /var/log/openhab2/events.log <==

2018-11-29 21:58:41.239 [me.event.ThingUpdatedEvent] - Thing 'exec:command:zaehler' has been updated.

2018-11-29 21:58:41.261 [vent.ItemStateChangedEvent] - Zaehler_strom changed from We trust you have received the usual lecture from the local System

Administrator. It usually boils down to these three things:

    #1) Respect the privacy of others.

    #2) Think before you type.

    #3) With great power comes great responsibility.

sudo: no tty present and no askpass program specified

We trust you have received the usual lecture from the local System

Administrator. It usually boils down to these three things:

    #1) Respect the privacy of others.

    #2) Think before you type.

    #3) With great power comes great responsibility.

sudo: no tty present and no askpass program specified to cat: invalid option -- 'l'

Try 'cat --help' for more information.

cat: invalid option -- 'l'

Try 'cat --help' for more information.

I can not understand what’s wrong ?!

2

Very likely the exec command is executed via sudo and you get the output of that.

Not sure how, but you don’t want sudo in the chain of commands.

3

check this out:

4

It’s doesent running well.

I put the command in a zaehler.sh and executed from the terminal. (Its working correct!)

Can I run the zaehler.sh by the exec?

Thx Jens

5

as which user?
did you read the linked thread?

6

Hi, i’m reading the thread.
I change the sudoes and disable the password function. I try as user openHabian

7

then you didn’t read the thread (yet)
it explains that the OH2 process runs as the openhab user (not openHabian)