fsnotify

README

File system notifications for Go

Cross platform: Windows, Linux, BSD and OS X.

Adapter	OS	Status
inotify	Linux, Android*	Supported
kqueue	BSD, OS X, iOS*	Supported
ReadDirectoryChangesW	Windows	Supported
FSEvents	OS X	Planned
FEN	Solaris 11	Planned
fanotify	Linux 2.6.37+
Polling	All	Maybe
	Plan 9

* Android and iOS are untested.

Please see the documentation for usage. Consult the Wiki for the FAQ and further information.

API stability

Two major versions of fsnotify exist.

fsnotify.v1 provides a new API based on this design document. You can import v1 with:

import "gopkg.in/fsnotify.v1"

* Refer to the package as fsnotify (without the .v1 suffix).

fsnotify.v0 is API-compatible with howeyc/fsnotify. Bugfixes may be backported, but I recommend upgrading to v1.

import "gopkg.in/fsnotify.v0"

Further API changes are planned, but a new major revision will be tagged, so you can depend on the v1 API.

Contributing

• Send questions to golang-dev@googlegroups.com.
• Request features and report bugs using the GitHub Issue Tracker.

A future version of Go will have fsnotify in the standard library, therefore fsnotify carries the same LICENSE as Go. Contributors retain their copyright, so we need you to fill out a short form before we can accept your contribution: Google Individual Contributor License Agreement.

Please read CONTRIBUTING before opening a pull request.

Example

See example_test.go.

Documentation

Overview

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

Index

• type Event
  • func (e Event) String() string
• type Op
• 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

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 file operations that can trigger a notification.

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

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

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)
}

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 the named file or directory (non-recursively).