How to fix this error "runtime.main: undefined main.init"

Question

Trying run a simple hello world go program returns an error.

# command-line-arguments runtime.main: undefined: main.init runtime.main: undefined: main.main 

The file contents:

package main     import "fmt" func main() {   fmt.Println("Hello, World!") } 

main is obviously defined and adding func init() {} doesn't help.

Both the run and build commands result in the same error.

go build hello_test.go go run hello_test.go 

Answer 1

Rename hello_test.go to e.g. hello.go and it should work as expected. Go source files ending in _test are special (for the go build system). They're reserved for the go test command.