如何使用Go的os / exec评估环境变量

How do I get Go to evaluate the $PATH variable. I currently just prints "$PATH"

I have the following code

package main

import (
        "fmt"
        "log"
        "os/exec"
)

func main() {
        out, err := exec.Command("echo","$PATH").Output()
        if err != nil {
                log.Fatal(err)
        }
        fmt.Printf("%s
",out)
}

You need to use os.Getenv("PATH")

package main

import (
  "fmt"
  "log"
  "os/exec"
  "os"
)

func main() {
  out, err := exec.Command("echo",os.Getenv("PATH")).Output()
  if err != nil {
    log.Fatal(err)
  }
  fmt.Printf("%s
",out)
}