From e48cb5d04872b4e3fd690d4d23acdf166e75fe7e Mon Sep 17 00:00:00 2001
From: "Guillermo J. Rozas" <edu/mit/csail/zurich/gjr>
Date: Tue, 12 Jan 1993 20:47:07 +0000
Subject: [PATCH] Initial revision

---
 etc/dumpdat.scm | 73 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 73 insertions(+)
 create mode 100644 etc/dumpdat.scm

diff --git a/etc/dumpdat.scm b/etc/dumpdat.scm
new file mode 100644
index 000000000..b591a4908
--- /dev/null
+++ b/etc/dumpdat.scm
@@ -0,0 +1,73 @@
+#| -*-Scheme-*-
+
+$Id: dumpdat.scm,v 1.1 1993/01/12 20:47:07 gjr Exp $
+
+Copyright (c) 1993 Massachusetts Institute of Technology
+
+This material was developed by the Scheme project at the Massachusetts
+Institute of Technology, Department of Electrical Engineering and
+Computer Science.  Permission to copy this software, to redistribute
+it, and to use it for any purpose is granted, subject to the following
+restrictions and understandings.
+
+1. Any copy made of this software must include this copyright notice
+in full.
+
+2. Users of this software agree to make their best efforts (a) to
+return to the MIT Scheme project any improvements or extensions that
+they make, so that these may be included in future releases; and (b)
+to inform MIT of noteworthy uses of this software.
+
+3. All materials developed as a consequence of the use of this
+software shall duly acknowledge such use, in accordance with the usual
+standards of acknowledging credit in academic research.
+
+4. MIT has made no warrantee or representation that the operation of
+this software will be error-free, and MIT is under no obligation to
+provide any services, by way of maintenance, update, or otherwise.
+
+5. In conjunction with products arising from the use of this material,
+there shall be no use of the name of the Massachusetts Institute of
+Technology nor of any adaptation thereof in any advertising,
+promotional, or sales literature without prior written consent from
+MIT in each case. |#
+
+;;;; Routines to preserve file dates and times.
+
+(declare (usual-integrations))
+
+(define decode-time
+  (access decode-time (->environment '(runtime date/time))))
+
+(define encode-time
+  (access encode-time (->environment '(runtime date/time))))
+
+(define decoded-time-structure-tag
+  (access decoded-time-structure-tag (->environment '(runtime date/time))))
+
+(define *dumped-dates* "_dates.scm")
+
+(define (dump-dates . paths)
+  (with-output-to-file *dumped-dates*
+    (lambda ()
+      (for-each
+       (lambda (path)
+	 (for-each
+	  (lambda (path)
+	    (write-line (cons (enough-namestring path)
+			      (subvector->list (decode-time
+						(file-modification-time path))
+					       1 8))))
+	  (directory-read path)))
+       paths))))
+
+(define (restore-dates)
+  (for-each
+   (lambda (info)
+     (let ((path (car info))
+	   (time (encode-time
+		  (list->vector
+		   (cons decoded-time-structure-tag (cdr info))))))
+       (set-file-times! path (file-modification-time path) time)))
+   (read-file *dumped-dates*)))
+	      
\ No newline at end of file
-- 
2.25.1