fsnotify

README

File system notifications for Go

GoDoc

Cross platform, works on:

• Windows
• Linux
• BSD
• OSX

Example:

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

    // Process events
    go func() {
        for {
            select {
            case ev := <-watcher.Event:
                log.Println("event:", ev)
            case err := <-watcher.Error:
                log.Println("error:", err)
            }
        }
    }()

    err = watcher.Watch("/tmp")
    if err != nil {
        log.Fatal(err)
    }

    /* ... do stuff ... */
    watcher.Close()

For each event:

• Name
• IsCreate()
• IsDelete()
• IsModify()
• IsRename()

Notes:

• When a file is renamed to another directory is it still being watched?
  • No (it shouldn't be, unless you are watching where it was moved to).
• When I watch a directory, are all subdirectories watched as well?
  • No, you must add watches for any directory you want to watch.
• Do I have to watch the Error and Event channels in a separate goroutine?
  • As of now, yes. Looking into making this single-thread friendly.

Documentation

Overview

Package fsnotify implements filesystem notification.

Index

• Constants
• type FileEvent
  • func (e *FileEvent) IsCreate() bool
  • func (e *FileEvent) IsDelete() bool
  • func (e *FileEvent) IsModify() bool
  • func (e *FileEvent) IsRename() bool
  • func (e *FileEvent) String() string
• type Watcher
  • func NewWatcher() (*Watcher, error)
  • func (w *Watcher) Close() error
  • func (w *Watcher) RemoveWatch(path string) error
  • func (w *Watcher) Watch(path string) error
  • func (w *Watcher) WatchFlags(path string, flags uint32) error

Examples

• NewWatcher

Constants

const (
	FSN_CREATE = 1
	FSN_MODIFY = 2
	FSN_DELETE = 4
	FSN_RENAME = 8

	FSN_ALL = FSN_MODIFY | FSN_DELETE | FSN_RENAME | FSN_CREATE
)

const (

	// Options for AddWatch
	IN_DONT_FOLLOW uint32 = syscall.IN_DONT_FOLLOW
	IN_ONESHOT     uint32 = syscall.IN_ONESHOT
	IN_ONLYDIR     uint32 = syscall.IN_ONLYDIR

	// Events
	IN_ACCESS        uint32 = syscall.IN_ACCESS
	IN_ALL_EVENTS    uint32 = syscall.IN_ALL_EVENTS
	IN_ATTRIB        uint32 = syscall.IN_ATTRIB
	IN_CLOSE         uint32 = syscall.IN_CLOSE
	IN_CLOSE_NOWRITE uint32 = syscall.IN_CLOSE_NOWRITE
	IN_CLOSE_WRITE   uint32 = syscall.IN_CLOSE_WRITE
	IN_CREATE        uint32 = syscall.IN_CREATE
	IN_DELETE        uint32 = syscall.IN_DELETE
	IN_DELETE_SELF   uint32 = syscall.IN_DELETE_SELF
	IN_MODIFY        uint32 = syscall.IN_MODIFY
	IN_MOVE          uint32 = syscall.IN_MOVE
	IN_MOVED_FROM    uint32 = syscall.IN_MOVED_FROM
	IN_MOVED_TO      uint32 = syscall.IN_MOVED_TO
	IN_MOVE_SELF     uint32 = syscall.IN_MOVE_SELF
	IN_OPEN          uint32 = syscall.IN_OPEN

	OS_AGNOSTIC_EVENTS = IN_MOVED_TO | IN_MOVED_FROM | IN_CREATE | IN_ATTRIB | IN_MODIFY | IN_MOVE_SELF | IN_DELETE | IN_DELETE_SELF

	// Special events
	IN_ISDIR      uint32 = syscall.IN_ISDIR
	IN_IGNORED    uint32 = syscall.IN_IGNORED
	IN_Q_OVERFLOW uint32 = syscall.IN_Q_OVERFLOW
	IN_UNMOUNT    uint32 = syscall.IN_UNMOUNT
)

Types

type FileEvent

type FileEvent struct {
	Name string // File name (optional)
	// contains filtered or unexported fields
}

func (*FileEvent) IsCreate

func (e *FileEvent) IsCreate() bool

IsCreate reports whether the FileEvent was triggerd by a creation

func (*FileEvent) IsDelete

func (e *FileEvent) IsDelete() bool

IsDelete reports whether the FileEvent was triggerd by a delete

func (*FileEvent) IsModify

func (e *FileEvent) IsModify() bool

IsModify reports whether the FileEvent was triggerd by a file modification or attribute change

func (*FileEvent) IsRename

func (e *FileEvent) IsRename() bool

IsRename reports whether the FileEvent was triggerd by a change name

func (*FileEvent) String

func (e *FileEvent) String() string

String formats the event e in the form "filename: DELETE|MODIFY|..."

type Watcher

type Watcher struct {
	Error chan error // Errors are sent on this channel

	Event chan *FileEvent // Events are returned on this channel
	// contains filtered or unexported fields
}

func NewWatcher

func NewWatcher() (*Watcher, error)

NewWatcher creates and returns a new inotify instance using inotify_init(2)

Example

package main

import (
	"log"

	"code.google.com/p/go.exp/fsnotify"
)

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

	go func() {
		for {
			select {
			case ev := <-watcher.Event:
				log.Println("event:", ev)
			case err := <-watcher.Error:
				log.Println("error:", err)
			}
		}
	}()

	err = watcher.Watch("/tmp/foo")
	if err != nil {
		log.Fatal(err)
	}
}

func (*Watcher) Close

func (w *Watcher) Close() error

Close closes an inotify watcher instance It sends a message to the reader goroutine to quit and removes all watches associated with the inotify instance

func (*Watcher) RemoveWatch

func (w *Watcher) RemoveWatch(path string) error

Remove a watch on a file

func (*Watcher) Watch

func (w *Watcher) Watch(path string) error

Watch a given file path

func (*Watcher) WatchFlags

func (w *Watcher) WatchFlags(path string, flags uint32) error

Watch a given file path for a particular set of notifications (FSN_MODIFY etc.)