Installing Go and the go command

Installing Go

Go has an official installer for Windows, macOS and Linux on the download page at go.dev/dl. On Windows you run the .msi file; on macOS the .pkg file; on Linux you unpack a .tar.gz file into /usr/local/go and add /usr/local/go/bin to your PATH. PATH is the list of folders your terminal searches when you type a command name.

1. Download the installer for your system from go.dev/dl.
2. Run it (or unpack it on Linux) with the default settings.
3. Close and reopen your terminal so it picks up the new PATH.
4. Type go version. You should see something like go version go1.26.0 windows/amd64.

go version
# go version go1.26.0 windows/amd64   (your numbers may differ)

An editor

Any text editor works, but VS Code with the official Go extension (or GoLand, a paid IDE) gives you auto-complete, error underlines and automatic formatting on save. The VS Code extension uses gopls, the official Go language server: a background program that understands your code and tells the editor about it.

The go command: one tool for everything

The ./... pattern means "this folder and every folder below it". So go vet ./... checks the whole project.

gofmt: no more arguments about style

Every Go file in the world is formatted the same way by gofmt (which go fmt runs). Tabs for indentation, the opening brace on the same line, and so on. Teams do not argue about style, and code from any company looks familiar. Most editors run it every time you save.

package main
import "fmt"
func main(){
fmt.Println(  "hi" )
}

package main

import "fmt"

func main() {
	fmt.Println("hi")
}

go vet: a second pair of eyes

package main

import "fmt"

func main() {
	name := "Asha"
	fmt.Printf("Hello %s, you are %d years old\n", name)
}

go env and a few settings

• GOROOT: where Go itself is installed. You rarely touch it.
• GOPATH: a folder (by default go inside your home folder) where downloaded modules are cached and go install puts tools. You do NOT need to keep your projects inside it any more.
• GOOS and GOARCH: the operating system and processor you build for. You will use them for cross-compiling in module 9.