package main

	import (
    "bufio"
    "fmt"
    "io/ioutil"
    "os"
)

	func check(e error) {
    if e != nil {
        panic(e)
    }
}

	func main() {
// To start, here’s how to dump a string (or just bytes) into a file.
	    d1 := []byte("hello\ngo\n")
    err := ioutil.WriteFile("/tmp/dat1", d1, 0644)
    check(err)
// For more granular writes, open a file for writing.
	    f, err := os.Create("/tmp/dat2")
    check(err)
// It’s idiomatic to defer a Close immediately after opening a file.
	    defer f.Close()
// You can Write byte slices as you’d expect.
	    d2 := []byte{115, 111, 109, 101, 10}
    n2, err := f.Write(d2)
    check(err)
    fmt.Printf("wrote %d bytes\n", n2)

	//A WriteString is also available.    

n3, err := f.WriteString("writes\n")
    fmt.Printf("wrote %d bytes\n", n3)
// Issue a Sync to flush writes to stable storage.
	    f.Sync()
// bufio provides buffered writers in addition to the buffered readers we saw earlier.
	    w := bufio.NewWriter(f)
    n4, err := w.WriteString("buffered\n")
    fmt.Printf("wrote %d bytes\n", n4)
// Use Flush to ensure all buffered operations have been applied to the underlying writer.
	    w.Flush()

	}
// Try running the file-writing code.
	$ go run writing-files.go 
wrote 5 bytes
wrote 7 bytes
wrote 9 bytes
// Then check the contents of the written files.
	$ cat /tmp/dat1

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