当尝试打开错误的文件扩展名时，为什么不能打开文本文件？

I'm trying to read a .txt file using Go, but I keep getting told that the program cannot find the specified file, even when I use the complete path to it. However, the code I have has no problem reading .go files.

Help?

package main

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


func main() {
// Open an input file, exit on error.
    inputFile, err := os.Open("main.go");
    if err != nil {
        log.Fatal("Error opening input file:", err)
    }
    defer inputFile.Close()

    scanner := bufio.NewScanner(inputFile)
    for scanner.Scan() {
        fmt.Println(scanner.Text())
    }
    if err := scanner.Err(); err != nil {
        log.Fatal(scanner.Err())
    }
}

You can see where you are adding this snippet of code at the beginning of your main function:

http://play.golang.org/p/DqnivLi1Z2

cwd, err := os.Getwd()
if err != nil {
    log.Fatal("os.Getwd ", err)
}
log.Println("Current Directory", cwd)
files, err := ioutil.ReadDir(cwd)
if err != nil {
    log.Fatal("ioutil.ReadDir", err)
}

for idx, finfo := range files {
    log.Println(idx, " ", finfo.Name)
}