84 lines
3.9 KiB
Go
84 lines
3.9 KiB
Go
// Copyright (c) 2014-2015 The Notify Authors. All rights reserved.
|
|
// Use of this source code is governed by the MIT license that can be
|
|
// found in the LICENSE file.
|
|
|
|
// BUG(rjeczalik): Notify does not collect watchpoints, when underlying watches
|
|
// were removed by their os-specific watcher implementations. Instead users are
|
|
// advised to listen on persistent paths to have guarantee they receive events
|
|
// for the whole lifetime of their applications (to discuss see #69).
|
|
|
|
// BUG(ppknap): Linux (inotify) does not support watcher behavior masks like
|
|
// InOneshot, InOnlydir etc. Instead users are advised to perform the filtering
|
|
// themselves (to discuss see #71).
|
|
|
|
// BUG(ppknap): Notify was not tested for short path name support under Windows
|
|
// (ReadDirectoryChangesW).
|
|
|
|
// BUG(ppknap): Windows (ReadDirectoryChangesW) cannot recognize which notification
|
|
// triggers FileActionModified event. (to discuss see #75).
|
|
|
|
package notify
|
|
|
|
var defaultTree = newTree()
|
|
|
|
// Watch sets up a watchpoint on path listening for events given by the events
|
|
// argument.
|
|
//
|
|
// File or directory given by the path must exist, otherwise Watch will fail
|
|
// with non-nil error. Notify resolves, for its internal purpose, any symlinks
|
|
// the provided path may contain, so it may fail if the symlinks form a cycle.
|
|
// It does so, since not all watcher implementations treat passed paths as-is.
|
|
// E.g. FSEvents reports a real path for every event, setting a watchpoint
|
|
// on /tmp will report events with paths rooted at /private/tmp etc.
|
|
//
|
|
// The c almost always is a buffered channel. Watch will not block sending to c
|
|
// - the caller must ensure that c has sufficient buffer space to keep up with
|
|
// the expected event rate.
|
|
//
|
|
// It is allowed to pass the same channel multiple times with different event
|
|
// list or different paths. Calling Watch with different event lists for a single
|
|
// watchpoint expands its event set. The only way to shrink it, is to call
|
|
// Stop on its channel.
|
|
//
|
|
// Calling Watch with empty event list does expand nor shrink watchpoint's event
|
|
// set. If c is the first channel to listen for events on the given path, Watch
|
|
// will seamlessly create a watch on the filesystem.
|
|
//
|
|
// Notify dispatches copies of single filesystem event to all channels registered
|
|
// for each path. If a single filesystem event contains multiple coalesced events,
|
|
// each of them is dispatched separately. E.g. the following filesystem change:
|
|
//
|
|
// ~ $ echo Hello > Notify.txt
|
|
//
|
|
// dispatches two events - notify.Create and notify.Write. However, it may depend
|
|
// on the underlying watcher implementation whether OS reports both of them.
|
|
//
|
|
// Windows and recursive watches
|
|
//
|
|
// If a directory which path was used to create recursive watch under Windows
|
|
// gets deleted, the OS will not report such event. It is advised to keep in
|
|
// mind this limitation while setting recursive watchpoints for your application,
|
|
// e.g. use persistent paths like %userprofile% or watch additionally parent
|
|
// directory of a recursive watchpoint in order to receive delete events for it.
|
|
func Watch(path string, c chan<- EventInfo, events ...Event) error {
|
|
return defaultTree.Watch(path, c, nil, events...)
|
|
}
|
|
|
|
// This function works the same way as Watch. In addition it does not watch
|
|
// files or directories based on the return value of the argument function
|
|
// doNotWatch. Given a path as argument doNotWatch should return true if the
|
|
// file or directory should not be watched.
|
|
func WatchWithFilter(path string, c chan<- EventInfo,
|
|
doNotWatch func(string) bool, events ...Event) error {
|
|
return defaultTree.Watch(path, c, doNotWatch, events...)
|
|
}
|
|
|
|
// Stop removes all watchpoints registered for c. All underlying watches are
|
|
// also removed, for which c was the last channel listening for events.
|
|
//
|
|
// Stop does not close c. When Stop returns, it is guaranteed that c will
|
|
// receive no more signals.
|
|
func Stop(c chan<- EventInfo) {
|
|
defaultTree.Stop(c)
|
|
}
|