// Mgmt
// Copyright (C) James Shubin and the project contributors
// Written by James Shubin <james@shubin.ca> and the project contributors
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.
//
// Additional permission under GNU GPL version 3 section 7
//
// If you modify this program, or any covered work, by linking or combining it
// with embedded mcl code and modules (and that the embedded mcl code and
// modules which link with this program, contain a copy of their source code in
// the authoritative form) containing parts covered by the terms of any other
// license, the licensors of this program grant you additional permission to
// convey the resulting work. Furthermore, the licensors of this program grant
// the original author, James Shubin, additional permission to update this
// additional permission if he deems it necessary to achieve the goals of this
// additional permission.

//go:build !root

package util

import (
	"fmt"
	"os"
	"time"
)

func ExampleFlock() {
	lockFile := "/tmp/flock.lock"
	fmt.Printf("hello\n")
	defer fmt.Printf("goodbye\n")
	defer os.Remove(lockFile)

	m := NewFlock(lockFile)
	unlock, err := m.TryLock()
	if err != nil {
		fmt.Printf("err: %+v\n", err)
		return
	}
	if unlock == nil {
		fmt.Printf("already locked\n")
		return
	}
	fmt.Printf("locked...\n")
	time.Sleep(1 * time.Second)
	unlock()
	fmt.Printf("unlocked...\n")

	// Output: hello
	// locked...
	// unlocked...
	// goodbye
}