From dd45e6a67c53f673bb49ca8a001fd3a63ceb640e Mon Sep 17 00:00:00 2001
From: Nate Finch <nate.finch@gmail.com>
Date: Fri, 4 Nov 2016 09:48:45 -0400
Subject: [PATCH] update docs w/ backup format info

---
 README.md     | 8 ++++++++
 lumberjack.go | 8 ++++++++
 2 files changed, 16 insertions(+)

diff --git a/README.md b/README.md
index 9f8e698..9e97154 100644
--- a/README.md
+++ b/README.md
@@ -87,6 +87,14 @@ the current file is closed, renamed, and a new log file created with the
 original name. Thus, the filename you give Logger is always the "current" log
 file.
 
+Backups use the log file name given to Logger, in the form `name-timestamp.ext`
+where name is the filename without the extension, timestamp is the time at which
+the log was rotated formatted with the time.Time format of
+`2006-01-02T15-04-05.000` and the extension is the original extension.  For
+example, if your Logger.Filename is `/var/log/foo/server.log`, a backup created
+at 6:30pm on Nov 11 2016 would use the filename
+`/var/log/foo/server-2016-11-04T18-30-00.000.log`
+
 ### Cleaning Up Old Log Files
 Whenever a new logfile gets created, old log files may be deleted.  The most
 recent files according to the encoded timestamp will be retained, up to a
diff --git a/lumberjack.go b/lumberjack.go
index 7014444..b4bb54f 100644
--- a/lumberjack.go
+++ b/lumberjack.go
@@ -55,6 +55,14 @@ var _ io.WriteCloser = (*Logger)(nil)
 // original name. Thus, the filename you give Logger is always the "current" log
 // file.
 //
+// Backups use the log file name given to Logger, in the form
+// `name-timestamp.ext` where name is the filename without the extension,
+// timestamp is the time at which the log was rotated formatted with the
+// time.Time format of `2006-01-02T15-04-05.000` and the extension is the
+// original extension.  For example, if your Logger.Filename is
+// `/var/log/foo/server.log`, a backup created at 6:30pm on Nov 11 2016 would
+// use the filename `/var/log/foo/server-2016-11-04T18-30-00.000.log`
+//
 // Cleaning Up Old Log Files
 //
 // Whenever a new logfile gets created, old log files may be deleted.  The most