如何在进行交叉编译时切换/选择要使用的代码

Question

I am using the +build tag to define what to compile based on the architecture.

For code that only runs on UNIX/BSD I use this:

// +build freebsd netbsd openbsd dragonfly darwin 
// +build amd64

And for linux I have:

// +build linux

The name of the files containing the source code is like this:

watchpid.go
watchpid_linux.go

The files contains the same method signature but different approaches.

func watchPid() {
  // kqueue for UNIX, BSD
  // for loop cross-platform version (linux)
}

In case I would like to test/compile for example the linux version on a Mac OS X, is there a easy switch/trick to do it instead of editing the +build tag or renaming the files?

Answer 1

Use GOOS=linux go build

Check out https://golang.org/cmd/go/#hdr-Environment_variables and http://dave.cheney.net/2015/08/22/cross-compilation-with-go-1-5