Writing to a file

So far, we have seen ways to read files. This subsection shows how to write data to files in four different ways and how to append data to an existing file. The code of writeFile.go is as follows:

package main
import (
    "bufio"
    "fmt"
    "io"
    "os"
)
func main() {
    buffer := []byte("Data to write\n")
    f1, err := os.Create("/tmp/f1.txt")

os.Create() returns an *os.File value associated with the file path that is passed as a parameter. Note that if the file already exists, os.Create() truncates it.

    if err != nil {
        fmt.Println("Cannot create file", err)
        return
    }
    defer f1.Close()
    fmt.Fprintf(f1, string(buffer))

The fmt.Fprintf() function, which requires a string variable, helps you write data to your own files using the format you want. The only requirement is having an io.Writer to write to. In this case, a valid *os.File variable,...