Golang example: read a file line by line.

golang_ReadLineByLine.go

package main

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

func ReadLineByLine(filepath string, out chan string) {
    defer close(out)

    file, err := os.Open(filepath)
    if err != nil {
        return 
    }
    defer file.Close()
    
    scanner := bufio.NewScanner(file)
    lines := 0 

    for scanner.Scan() {
        out <- scanner.Text()        
        lines++
    }
}


func main() {

    argc := len(os.Args)
    if argc < 2 {
        fmt.Printf("usage: %s <json file>\n", os.Args[0])
        os.Exit(1)
    }

    c := make(chan string)
    go ReadLineByLine(os.Args[1], c)

    for running := true; running; {
        var s string;
        select {
            case s, running = <- c:
                fmt.Println(s)
        }
    }
}