Go channels and I/O - io

Question

First function
ReadF2C
takes a filename and channel, reads from file and inputs in channel.
Second function
WriteC2F
takes 2 channels and filename, takes value of each channel and saves the lower value in the output file. I'm sure there is a few syntax errors but i'm new to GO
package main
import (
"fmt"
"bufio"
"os"
"strconv"
)
func main() {
fmt.Println("Hello World!\n\n")
cs1 := make (chan int)
var nameinput string = "input.txt"
readF2C(nameinput,cs1)
cs2 := make (chan int)
cs3 := make (chan int)
cs2 <- 10
cs2 <- 16
cs2 <- 7
cs2 <- 2
cs2 <- 5
cs3 <- 8
cs3 <- 15
cs3 <- 14
cs3 <- 1
cs3 <- 6
var nameoutput string = "output.txt"
writeC2F (nameoutput,cs2,cs3)
}
func readF2C (fn string, ch chan int){
f,err := os.Open(fn)
r := bufio.NewReader(f)
for err != nil { // not end of file
fmt.Println(r.ReadString('\n'))
ch <- r.ReadString('\n')
}
if err != nil {
fmt.Println(r.ReadString('\n'))
ch <- -1
}
}
func writeC2F(fn string, // output text file
ch1 chan int, // first input channel
ch2 chan int){
var j int = 0
var channel1temp int
var channel2temp int
f,_ := os.Create(fn)
w := bufio.NewWriter(f)
channel1temp = <-ch1
channel2temp = <-ch2
for j := 1; j <= 5; j++ {
if (channel2temp < channel1temp){
n4, err := w.WriteString(strconv.Itoa(channel1temp))
} else{
n4, err := w.WriteString(strconv.Itoa(channel2temp))
}
w.flush()
}
}
This is the error messages I get:
prog.go:38: multiple-value r.ReadString() in single-value context
prog.go:65: w.flush undefined (cannot refer to unexported field or method bufio.(*Writer)."".flush)

Answer 1

There are multiple errors:
1)
Unlike C, Go enforces you to have your curly braces directly after your statements. So for an if case (and the same for func), instead of doing it like this:
if (channel2temp < channel1temp)
{
use this
if channel2temp < channel1temp {
2)
There is no while in Go. Use for
for {
...
}
or
for channel1temp != null || channel2temp != null {
...
}
3)
Usage of non-declared variables. Often easy to fix by making a short variable declaration the first time you initialize the variable. So instead of:
r = bufio.NewReader(file)
use
r := bufio.NewReader(file)
4)
Trying to a assign multi-value return into a single variable. If a function returns two values and you only need one, the variable you don't want can be discarded by assigning it to _. So instead of:
file := os.Open(fn)
use
file, _ := os.Open(fn)
but best practice would be to catch that error:
file, err := os.Open(fn)
if err != nil {
panic(err)
}
There are more errors on top of this, but maybe it will get you started.
I also suggest reading Effective Go since it will explain many of the things I've just mentioned.
Edit:
And there are help online for sure. It might be a new language, but the online material is really useful. Below is a few that I used when learning Go:
Effective Go: Good document on how to write idiomatic Go code
The Go programming language Tour: Online tour of Go with interactive examples.
Go By Example: Interactive examples of Go programs, starting with Hello World.
Go Specification: Surprisingly readable for being a specification. Maybe not a start point, but very useful.