initial commit (second try)

utils.go

@@ -0,0 +1,35 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"strings"
+)
+
+func runCommand(name string, args ...string) error {
+	cmd := exec.Command(name, args...)
+	fmt.Fprintf(os.Stderr, "+ %s %s\n", name, strings.Join(args, " "))
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	return cmd.Run()
+}
+
+func runCommandOutput(name string, args ...string) (string, error) {
+	cmd := exec.Command(name, args...)
+	fmt.Fprintf(os.Stderr, "+ %s %s\n", name, strings.Join(args, " "))
+	output, err := cmd.Output()
+	if err != nil {
+		return "", err
+	}
+	return strings.TrimSpace(string(output)), nil
+}
+
+func runCommandWithInput(name string, input string, args ...string) error {
+	cmd := exec.Command(name, args...)
+	fmt.Fprintf(os.Stderr, "+ %s %s\n", name, strings.Join(args, " "))
+	cmd.Stdin = strings.NewReader(input)
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	return cmd.Run()
+}