fsnotify

Documentation

Overview

Package fsnotify provides a platform-independent interface for file system notifications.

Index

• Variables
• type Event
  • func (e Event) String() string
• type Op
  • func (op Op) String() string
• type Watcher
  • func NewWatcher() (*Watcher, error)
  • func (w *Watcher) Add(name string) error
  • func (w *Watcher) Close() error
  • func (w *Watcher) Remove(name string) error

Examples

• NewWatcher

Variables

var ErrEventOverflow = errors.New("fsnotify queue overflow")

Common errors that can be reported by a watcher

Types

type Event

type Event struct {
	Name string // Relative path to the file or directory.
	Op   Op     // File operation that triggered the event.
}

Event represents a single file system notification.

func (Event) String

func (e Event) String() string

String returns a string representation of the event in the form "file: REMOVE|WRITE|..."

type Op

type Op uint32

Op describes a set of file operations.

const (
	Create Op = 1 << iota
	Write
	Remove
	Rename
	Chmod
)

These are the generalized file operations that can trigger a notification.

func (Op) String

func (op Op) String() string

type Watcher

type Watcher struct {
	Events chan Event
	Errors chan error
	// contains filtered or unexported fields
}

Watcher watches a set of files, delivering events to a channel.

func NewWatcher

func NewWatcher() (*Watcher, error)

NewWatcher establishes a new watcher with the underlying OS and begins waiting for events.

Example

package main

import (
	"log"

	"github.com/fsnotify/fsnotify"
)

func main() {
	watcher, err := fsnotify.NewWatcher()
	if err != nil {
		log.Fatal(err)
	}
	defer watcher.Close()

	done := make(chan bool)
	go func() {
		for {
			select {
			case event := <-watcher.Events:
				log.Println("event:", event)
				if event.Op&fsnotify.Write == fsnotify.Write {
					log.Println("modified file:", event.Name)
				}
			case err := <-watcher.Errors:
				log.Println("error:", err)
			}
		}
	}()

	err = watcher.Add("/tmp/foo")
	if err != nil {
		log.Fatal(err)
	}
	<-done
}

func (*Watcher) Add

func (w *Watcher) Add(name string) error

Add starts watching the named file or directory (non-recursively).

func (*Watcher) Close

func (w *Watcher) Close() error

Close removes all watches and closes the events channel.

func (*Watcher) Remove

func (w *Watcher) Remove(name string) error

Remove stops watching the named file or directory (non-recursively).