New command and -as mkisofs option -genisoimage_completion

xorriso/xorrisofs.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 XORRISOFS 1 "Version 1.5.7, Jul 23, 2024"
+@c man .TH XORRISOFS 1 "Version 1.5.7, Aug 30, 2024"
 @c man .\" Please adjust this date whenever revising the manpage.
 @c man .\"
 @c man .\" Some roff macros, for reference:
@@ -2245,6 +2245,27 @@ The rules for list_of_names are the same as with -checksum_algorithm_iso.
 @table @asis
 @sp 1
 @c man .TP
+@item -genisoimage_completion
+@kindex -genisoimage_completion   completion of genisoimage options
+@cindex Options completion, -genisoimage_completion
+Match unrecognized option arguments which begin by a dash '-' against the
+known genisoimage options, like program
+genisoimage does unconditionally (and undocumentedly). If the given argument
+matches the beginning of exactly one genisoimage option, then it gets replaced
+by that option. Options which are genuine to mkisofs or xorriso's mkisofs
+emulation are not matched that way.
+Option arguments which consist entirely of a leading dash and letters out of
+"dDfJlNRrTUvz" are not matched but rather interpreted as usual, i.e. as 
+multiple options with leading dash and each single letter.
+If no genisoimage option is found or more than one are found, then a SORRY
+message is issued and the argument stays as is.
+@*
+To enable this mode by default, write the xorriso command
+@*
+  -genisoimage_completion on
+@*
+into one of the xorriso start files. See section FILES.
+@c man .TP
 @item -print-size
 @kindex -print-size   predict ISO image size
 @cindex ISO image size, predict, -print-size