Problem: want to redirect os.Stdout and access it’s contents from a string variable
Solution: this answer proved very useful:
package main
import (
"bytes"
"fmt"
"io"
"os"
)
func print() {
fmt.Println("output")
}
func main() {
old := os.Stdout // keep backup of the real stdout
r, w, _ := os.Pipe()
os.Stdout = w
print()
outC := make(chan string)
// copy the output in a separate goroutine so printing can't block indefinitely
go func() {
var buf bytes.Buffer
io.Copy(&buf, r)
outC <- buf.String()
}()
// back to normal state
w.Close()
os.Stdout = old // restoring the real stdout
out := <-outC
// reading our temp stdout
fmt.Println("previous output:")
fmt.Print(out)
}