错误“无法下载，未设置$ GOPATH。”

Question

Setup:

Have a look at my configuration:

$ echo $GOPATH && ls -r $GOPATH
/home/cyrus/.go
src  pkg  bin

$ echo $GOROOT && ls $GOROOT
/usr/local/go
api  AUTHORS  bin  CONTRIBUTORS  doc  favicon.ico  include  lib  LICENSE  misc  PATENTS  pkg  README  robots.txt  src  test  VERSION

You can see that I've set a path for $GOPATH. In addition, I've created subdirectories that I may not need.

Question:

Why does the following command generate this error message?

$ go get code.google.com/p/go-tour/gotour                                                                                                               
package code.google.com/p/go-tour/gotour: cannot download, $GOPATH not set. For more details see: go help gopath

Answer 1

If you set a variable like this:

GOPATH=$HOME/go

It won't be exported to any subprocesses. It's only available to that process. If you want to export it to subprocesses, use export:

export GOPATH

You can also combine the assignment and export:

export GOPATH=$HOME/go