Introduction: Datalogging, Timestamp, & Monitor Arduino Data With an Incredible Bash-One-Liner

The description doesn't fit on one line -- but the code does!

This is a bash one-liner for logging data from the Arduino, and for processing (e.g. timestamping, reacting to sensor readings, etc.) and then redirecting data file.

I have tried this out on Mac Os X, but I'll verify it on the Raspberry Pi right away (as linux can perform nanosecond timestamping).


cat /dev/cu.usbmodem1421 | awk '{ for (i=0; i<NF; i++) printf $i + system("date +,%s")}'

To use with your arduino:

Just replace the /dev/cu.usbmodem1421 with your arduino's serial port (an easy way to find this is to see which is checked in the Tools -> Port  of the Arduino IDE menu)

(If you have both /dev/cu.usbmodem and /dev/tty.usbmodem, then use the /dev/cu.usbmodem one)

Real-Time Monitoring:

Real-time monitoring and command line reactions are simple to add-on, for these examples visit (and please star) the project's github.


Geophysicist (author)2016-07-01


Thank you so much for this interesting project. But, did you manage to try it on raspberry?

And, if I want to to timestamp sensor readings using GPS synchronized timing do you know how it can be implemented?

Thank you,

Alireza, Geophysicist

jsonius (author)2014-12-04

Do you need an internet connection for the timestamp to work?

jabberwocky1396 (author)jsonius2014-12-04

Hi Jsonius,

Thanks for the question: no internet connection is required for this method to work. It uses the system's own `date` utility, and can be used completely offline.

-- Greg

scruss (author)2014-10-11

Good effort here - there's a lot to learn and use in Linux!

The command ts (in the Debian/Raspbian/Ubuntu package moreutils) might also do what I think you're trying to do here. Also, if you use gnu awk, it has a strftime function, so you can avoid the system() call and do

gawk '{print strftime("%s ") $0}'

You might also want to try grabserial.