github.com/oschwald/maxminddb-golang 安装报错

安装 maxminddb-golang错误：

　　dill@ubuntu-vm:~/workspace/go/src/github.com$ go get github.com/oschwald/maxminddb-golang
　　package golang.org/x/sys/unix: unrecognized import path "golang.org/x/sys/unix" (https fetch: Get https://golang.org/x/sys/unix?go-get=1: dial tcp 216.239.37.1:443: i/o timeout)

解决办法： 

1. 添加golang.org/x/sys/unix:
 　　dill@ubuntu-vm:~/workspace/go/src$ go get github.com/golang/sys
 　　又报错 ：can't load package: package github.com/golang/sys:  
　　　　no buildable Go source files in /home/dill/workspace/go/src/github.com/golang/sys
　　  解决办法：

1. 1. git clone https://github.com/golang/sys.git
      
   2. mkdir -p  golang.org/x/sys/unix ($GOPATH/src目录下)
   3.  cp -r unix/ golang.org/x/sys/($GOPATH/src目录下)

2. 重新go get github.com/oschwald/maxminddb-golang 竟然好了，不知道原理，先记下吧！:+)