Dynamically discover executable path at runtime

discover.go

package main

import (
	"fmt"
	"os"
	"path/filepath"
)

func executableLocation() (string, string, error) {
	// 0th arg traditionally contains name of executable as invoked by the user
	// Split executable name into directory path and filename parts
	exeDir, exeFile := filepath.Split(os.Args[0])

	// Clean the directory path and convert it to an absolute path
	// This handles cases where a relative path reference is used
	// such as "./foo" or "../foo"
	absoluteExeDir, err := filepath.Abs(filepath.Clean(exeDir))

	// Return error if absolute path construction fails
	if err != nil {
		return "", "", err
	}
	return absoluteExeDir, exeFile, nil
}

func main() {
	exeDir, exeFileName, err := executableLocation()
	if err != nil {
		panic(err)
	}
	fmt.Printf("Executable dir: %s\nExecutable filename: %s\n", exeDir, exeFileName)
}

example_output.sh

> go build -o discover main/main.go
> ./discover
Executable dir: /Users/kesmit/repos/experiments/discover
Executable filename: discover
> go run main/main.go
Executable dir: /var/folders/1c/19j1cgwx2ng1gjxj5rypmkwh0000gp/T/go-build3431073968/b001/exe
Executable filename: main
>