About “sudo go run main.go”

Question

I use Go in my Ubuntu 16.04, and I set GOPATH, GOROOT and run simple code successfully.

Now I want to capture network packet by \"gopacket\

Answer 1

Your environment variables are not set for your root user. Don't try to run sudo go run ..., instead build the binary without sudo, e.g. go build or go install, and then execute the binary with sudo.

Let's say you're in the folder of main.go, assumed it's called mycapt:

go build
sudo ./mycapt

Or:

go install
sudo $GOPATH/bin/mycapt

Answer 2

sudo -E go run main.go may work for you.

Here is what you can get about -E option from man sudo

-E, --preserve-env
   Indicates to the security policy that the user wishes to preserve
   their existing environment variables. The security policy may return
   an error if the user does not have permission to preserve the environment.