github.com/dgallion1/notify@v0.9.3-0.20201128171805-931189d936e0/example_inotify_test.go (about) 1 // Copyright (c) 2014-2015 The Notify Authors. All rights reserved. 2 // Use of this source code is governed by the MIT license that can be 3 // found in the LICENSE file. 4 5 // +build linux 6 7 package notify_test 8 9 import ( 10 "log" 11 12 "golang.org/x/sys/unix" 13 14 "github.com/rjeczalik/notify" 15 ) 16 17 // This example shows how to watch changes made on file-system by text editor 18 // when saving a file. Usually, either InCloseWrite or InMovedTo (when swapping 19 // with a temporary file) event is created. 20 func ExampleWatch_linux() { 21 // Make the channel buffered to ensure no event is dropped. Notify will drop 22 // an event if the receiver is not able to keep up the sending pace. 23 c := make(chan notify.EventInfo, 1) 24 25 // Set up a watchpoint listening for inotify-specific events within a 26 // current working directory. Dispatch each InCloseWrite and InMovedTo 27 // events separately to c. 28 if err := notify.Watch(".", c, notify.InCloseWrite, notify.InMovedTo); err != nil { 29 log.Fatal(err) 30 } 31 defer notify.Stop(c) 32 33 // Block until an event is received. 34 switch ei := <-c; ei.Event() { 35 case notify.InCloseWrite: 36 log.Println("Editing of", ei.Path(), "file is done.") 37 case notify.InMovedTo: 38 log.Println("File", ei.Path(), "was swapped/moved into the watched directory.") 39 } 40 } 41 42 // This example shows how to use Sys() method from EventInfo interface to tie 43 // two separate events generated by rename(2) function. 44 func ExampleWatch_linuxMove() { 45 // Make the channel buffered to ensure no event is dropped. Notify will drop 46 // an event if the receiver is not able to keep up the sending pace. 47 c := make(chan notify.EventInfo, 2) 48 49 // Set up a watchpoint listening for inotify-specific events within a 50 // current working directory. Dispatch each InMovedFrom and InMovedTo 51 // events separately to c. 52 if err := notify.Watch(".", c, notify.InMovedFrom, notify.InMovedTo); err != nil { 53 log.Fatal(err) 54 } 55 defer notify.Stop(c) 56 57 // Inotify reports move filesystem action by sending two events tied with 58 // unique cookie value (uint32): one of the events is of InMovedFrom type 59 // carrying move source path, while the second one is of InMoveTo type 60 // carrying move destination path. 61 moves := make(map[uint32]struct { 62 From string 63 To string 64 }) 65 66 // Wait for moves. 67 for ei := range c { 68 cookie := ei.Sys().(*unix.InotifyEvent).Cookie 69 70 info := moves[cookie] 71 switch ei.Event() { 72 case notify.InMovedFrom: 73 info.From = ei.Path() 74 case notify.InMovedTo: 75 info.To = ei.Path() 76 } 77 moves[cookie] = info 78 79 if cookie != 0 && info.From != "" && info.To != "" { 80 log.Println("File:", info.From, "was renamed to", info.To) 81 delete(moves, cookie) 82 } 83 } 84 }