Deferred cd in a function

---

examples/cd-and-back/deferred_cd.go

package main

import (
    "fmt"
    "log"
    "os"
)

func main() {
    var dir string
    dir, _ = os.Getwd()
    fmt.Printf("Before  %v\n", dir)
    cd("..", showDir)
    dir, _ = os.Getwd()
    fmt.Printf("After %v\n", dir)
}

func showDir() {
    fmt.Println("Hello")
    dir, _ := os.Getwd()
    fmt.Printf("Inside:  %v\n", dir)
}

func cd(path string, f func()) {
    //fmt.Println(path)
    cwd, err := os.Getwd()
    if err != nil {
        log.Panic(err)
    }
    defer os.Chdir(cwd)
    err = os.Chdir(path)
    f()
}