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.

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    4 Discussions


    3 years ago


    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


    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


    4 years ago on Introduction

    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.