Documented new timestamp behavior of El Torito catalog file

xorriso/xorriso.texi

@@ -50,7 +50,7 @@
 @c man .\" First parameter, NAME, should be all caps
 @c man .\" Second parameter, SECTION, should be 1-8, maybe w/ subsection
 @c man .\" other parameters are allowed: see man(7), man(1)
-@c man .TH XORRISO 1 "Version 1.4.5, Aug 05, 2016"
+@c man .TH XORRISO 1 "Version 1.4.5, Aug 07, 2016"
 @c man .\" Please adjust this date whenever revising the manpage.
 @c man .\"
 @c man .\" Some roff macros, for reference:
@@ -2171,6 +2171,10 @@ in order to make the format recognizable.
 Example:
 @*
   -alter_date m-c 2013.11.27.103951 /file1 /file2 --
+@*
+This command does not persistently apply to the boot catalog, which gets fresh
+timestamps at -commit time. Command -volume_date "uuid" can set this time
+value.
 @c man .TP
 @item -alter_date_r type timestring iso_rr_path [***]
 @kindex -alter_date_r   sets timestamps in ISO image
@@ -3314,6 +3318,12 @@ Some of them are prone to timezone computations. The timestrings "default" or
 "overridden" cause default settings: "c" and "m" will show the current time
 of image creation. "x" and "f" will be marked as insignificant.
 "uuid" will be deactivated.
+@*
+At -commit time, some timestamps get set to the maximum value of effectively
+written volume creation and modification time: El Torito boot catalog,
+HFS+ superblock, ECMA-119 file modification time if -compliance "no_rec_mtime".
+The isohybrid MBR id is computed from "uuid" if given, else from the effective
+volume modification date.
 @c man .TP
 @item -copyright_file text
 @kindex -copyright_file   sets copyright file name
@@ -3796,13 +3806,15 @@ which bundles these individual settings:
  -boot_image any boot_info_table=on
 @*
 An El Torito boot catalog file gets inserted into the ISO image with address
-@strong{cat_path=} at -commit time.
+@strong{cat_path=} with the first -boot_image "any" "next" or at -commit time.
 It is subject to normal -overwrite and -reassure processing if there is already
 a file with the same name.
 The catalog lists the boot images and is read by the boot facility to choose
 one of the boot images. But it is not necessary that it appears in the
 directory tree at all. One may hide it in all trees by @strong{cat_hidden=on}.
 Other possible values are "iso_rr", "joliet", "hfsplus", and the default "off".
+The timestamps of the boot catalog file are refreshed at commit time.
+Command -volume_date "uuid" can be used to set their value.
 @*
 @strong{bin_path=} depicts an El Torito boot image file, a binary program
 which is to be started by the hardware boot facility (e.g. the BIOS)