为什么不能从/ bin目录中运行go二进制文件？

Question

I downloaded go1.7.5.darwin-amd64.tar.gz for osx 10.12.2.

Unpacked the tar and went to the /bin directory to see if the Go executable would run.

$ cd Downloads/go/bin 
$ ls

total 54560  
-rwxr-xr-x@ 1 bryanwheelock  staff   9884220 Feb 10 16:53 go  
-rwxr-xr-x@ 1 bryanwheelock  staff  15065500 Feb 10 16:53 godoc  
-rwxr-xr-x@ 1 bryanwheelock  staff   2976976 Feb 10 16:53 gofmt  

bryanwheelock@Bryans-MacBook Fri Feb 10 16:57:45 ~/Downloads/go/bin
$ go version
-bash: go: command not found

Answer 1

When you type a command without giving the full path, your system will try to find it within all the folders provided in $PATH variable.

In typical Unix environment, your $PATH does not include "your current folder". So you need to either:

• call go by its full path (i.e. $HOME/Downloads/go/bin/go); or
• call go by its relative path (i.e. ./go); or
• put $HOME/Downloads/go/bin in your $PATH variable; or
• put . (Unix way of saying "your current folder") in your $PATH; or

• put your go binary into folders that already in your $PATH. For example

  sudo cp $HOME/Downloads/go/bin/* /usr/local/bin/.