TODO: Solution: Sum of numbers in a file

---

examples/sum/sum.go

package main

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

func main() {
    var err error
    if len(os.Args) != 2 {
        fmt.Printf("Missing filename.\nUsage: %v FILENAME\n", os.Args[0])
        os.Exit(1)
    }

    filename := os.Args[1]
    //fmt.Println(filename)
    var fh *os.File
    fh, err = os.Open(filename)
    //fmt.Printf("%T", fh)
    if err != nil {
        fmt.Printf("Error opening file '%v'\n%v\n", filename, err)
        os.Exit(1)
    }
    reader := bufio.NewReader(fh)
    var line string
    for true {
        line, _ = reader.ReadString('\n')
        //fmt.Print(line)
        for _, c := range line {
            if c == ' ' || c == '\n' {
                continue
            }
            fmt.Printf("%q\n", c)
        }
        if line == "" {
            break
        }
    }

}