From d9f4dcdb2569533d48cb825856c4f80250dcf487 Mon Sep 17 00:00:00 2001
From: Florin Dragos <florin.dragos@hp.com>
Date: Tue, 29 Sep 2015 16:51:16 +0300
Subject: [PATCH] Treat permission error as if file was deleted on windows

---
 watch/polling.go         | 11 ++++-------
 watch/polling_posix.go   |  9 ---------
 watch/polling_windows.go | 18 ------------------
 3 files changed, 4 insertions(+), 34 deletions(-)
 delete mode 100644 watch/polling_posix.go
 delete mode 100644 watch/polling_windows.go

diff --git a/watch/polling.go b/watch/polling.go
index 10a17eb..1747138 100644
--- a/watch/polling.go
+++ b/watch/polling.go
@@ -6,6 +6,7 @@ import (
 	"github.com/ActiveState/tail/util"
 	"gopkg.in/tomb.v1"
 	"os"
+	"runtime"
 	"time"
 )
 
@@ -51,8 +52,6 @@ func (fw *PollingFileWatcher) ChangeEvents(t *tomb.Tomb, origFi os.FileInfo) *Fi
 	go func() {
 		defer changes.Close()
 
-		var retry int = 0
-
 		prevSize := fw.Size
 		for {
 			select {
@@ -64,16 +63,14 @@ func (fw *PollingFileWatcher) ChangeEvents(t *tomb.Tomb, origFi os.FileInfo) *Fi
 			time.Sleep(POLL_DURATION)
 			fi, err := os.Stat(fw.Filename)
 			if err != nil {
-				if os.IsNotExist(err) {
+				// Windows cannot delete a file if a handle is still open (tail keeps one open) 
+				// so it gives access denied to anything trying to read it until all handles are released.
+				if os.IsNotExist(err) || (runtime.GOOS == "windows" && os.IsPermission(err)) {
 					// File does not exist (has been deleted).
 					changes.NotifyDeleted()
 					return
 				}
 
-				if permissionErrorRetry(err, &retry) {
-					continue
-				}
-
 				// XXX: report this error back to the user
 				util.Fatal("Failed to stat file %v: %v", fw.Filename, err)
 			}
diff --git a/watch/polling_posix.go b/watch/polling_posix.go
deleted file mode 100644
index 1a75546..0000000
--- a/watch/polling_posix.go
+++ /dev/null
@@ -1,9 +0,0 @@
-// Copyright (c) 2013 ActiveState Software Inc. All rights reserved.
-// +build linux darwin freebsd
-
-package watch
-
-func permissionErrorRetry(err error, retry *int) bool {
-	// No need for this on linux, don't retry
-	return false
-}
diff --git a/watch/polling_windows.go b/watch/polling_windows.go
deleted file mode 100644
index 9ffd23d..0000000
--- a/watch/polling_windows.go
+++ /dev/null
@@ -1,18 +0,0 @@
-// +build windows
-
-package watch
-
-import (
-	"os"
-)
-
-const permissionDeniedRetryCount int = 5
-
-func permissionErrorRetry(err error, retry *int) bool {
-	if os.IsPermission(err) && *retry < permissionDeniedRetryCount {
-		// While pooling a file that does not exist yet, but will be created by another process we can get Permission Denied
-		(*retry)++
-		return true
-	}
-	return false
-}