Sudo java -jar vs java -jar

Question

I have a server running on Java using the library Pi4j to control the RaspberryPi's GPIOs and a file on which I write the current GPIOs' statuses. When I run the code from IntelliJ IDE everything works just fine.
But when I create the .jar file and run it like

sudo java -jar server.jar

It works fine updating the file, but the GPIOs do not change their status.
When I do

java -jar server.jar

The GPIOs correctly change their status but I get the error java.io.FileNotFoundException: relStat.txt (Permission denied)

My file permission are all set to anyone, so anyone should be able to read, modify and run it. Why does this happen?

GPIO needs low level hardware access which the pi user doesn't have access to, hence the need to prefix with `sudo`. — George Profenza, May 20 '20 at 08:44

score 0 · Answer 1 · answered Jan 12 '20 at 15:23

0

This is a permission issue, The file owner is the "pi" user. Which user you are running under?

answered Jan 12 '20 at 15:23

Rami Khawaly

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I'm running under pi. – CrystalSpider Jan 12 '20 at 15:33
Did you add the "pi" user to the sudoer file (https://askubuntu.com/questions/7477/how-can-i-add-a-new-user-as-sudoer-using-the-command-line )? anyway this is required, do that and post the results – Rami Khawaly Jan 12 '20 at 15:39

Sudo java -jar vs java -jar

1 Answers1