解决unrecognized import path "golang.org/x/.."类问题

背景

安装Gin时，通过go get下载并安装gin软件包

$ go get -u github.com/gin-gonic/gin

问题

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

1. golang 在 github 上建立了一个镜像库，下载github上的镜像库放入GOPATH下即可

   mkdir -p $GOPATH/src/golang.org/x
   cd $GOPATH/src/golang.org/x
   git clone https://github.com/golang/sync.git
   git clone https://github.com/golang/crypto.git
   git clone https://github.com/golang/sys.git
   

2. 重新执行go get