From d9ddf0287eaeb9a9d66ba7ade9bf8aa96f1f0d3d Mon Sep 17 00:00:00 2001
From: John Cupitt <jcupitt@gmail.com>
Date: Thu, 26 Jun 2014 11:08:00 +0100
Subject: [PATCH] note date and version in dzprops

---
 libvips/foreign/dzsave.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/libvips/foreign/dzsave.c b/libvips/foreign/dzsave.c
index b55cb1f7..6c362f42 100644
--- a/libvips/foreign/dzsave.c
+++ b/libvips/foreign/dzsave.c
@@ -720,15 +720,29 @@ write_vips_properties( VipsForeignSaveDz *dz )
 {
 	VipsForeignSave *save = (VipsForeignSave *) dz;
 
+	time_t timebuf;
+	char time_string[30];
 	GsfOutput *out;
 
+	time( &timebuf );
+	ctime_r( &timebuf, time_string );
+
+	/* Remove the trailing \n.
+	 */
+	if( strlen( time_string ) > 0 &&
+		time_string[strlen( time_string ) - 1] == '\n' ) 
+		time_string[strlen( time_string ) - 1] = '\0';
+
 	out = vips_gsf_path( dz->tree, 
 		"vips-properties.xml", dz->root_name, NULL ); 
 
 	gsf_output_printf( out, 
 		"<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" ); 
 	gsf_output_printf( out, "<image>\n" ); 
-	gsf_output_printf( out, "  <properties>\n" ); 
+	gsf_output_printf( out, "  <properties\n" ); 
+	gsf_output_printf( out, "    version=\"%s\"\n", VIPS_VERSION ); 
+	gsf_output_printf( out, "    date=\"%s\"\n", time_string ); 
+	gsf_output_printf( out, "  >\n" ); 
 	(void) vips_image_map( save->ready, write_vips_property, out );
 	gsf_output_printf( out, "  </properties>\n" ); 
 	gsf_output_printf( out, "</image>\n" );