diff -rupN xz-5.2.9.old/src/xz/message.c xz-5.2.9/src/xz/message.c
--- xz-5.2.9.old/src/xz/message.c	2022-11-24 09:55:48.000000000 +0100
+++ xz-5.2.9/src/xz/message.c	2022-12-06 21:32:37.001869018 +0100
@@ -1102,7 +1102,8 @@ message_help(bool long_help)
 
 	puts(_(
 "  -z, --compress      force compression\n"
-"  -d, --decompress    force decompression\n"
+"  -d, --decompress, --uncompress\n"
+"                      force decompression\n"
 "  -t, --test          test compressed file integrity\n"
 "  -l, --list          list information about .xz files"));
 
@@ -1112,7 +1113,8 @@ message_help(bool long_help)
 	puts(_(
 "  -k, --keep          keep (don't delete) input files\n"
 "  -f, --force         force overwrite of output file and (de)compress links\n"
-"  -c, --stdout        write to standard output and don't delete input files"));
+"  -c, --stdout, --to-stdout\n"
+"                      write to standard output and don't delete input files"));
 	// NOTE: --to-stdout isn't included above because it's not
 	// the recommended spelling. It was copied from gzip but other
 	// compressors with gzip-like syntax don't support it.
@@ -1171,7 +1173,7 @@ message_help(bool long_help)
 		puts(_( // xgettext:no-c-format
 "      --memlimit-compress=LIMIT\n"
 "      --memlimit-decompress=LIMIT\n"
-"  -M, --memlimit=LIMIT\n"
+"  -M, --memlimit=LIMIT, (old alias --memory=LIMIT)\n"
 "                      set memory usage limit for compression, decompression,\n"
 "                      or both; LIMIT is in bytes, % of RAM, or 0 for defaults"));
 
diff -rupN xz-5.2.9.old/src/xz/xz.1 xz-5.2.9/src/xz/xz.1
--- xz-5.2.9.old/src/xz/xz.1	2022-11-24 09:55:48.000000000 +0100
+++ xz-5.2.9/src/xz/xz.1	2022-12-06 21:33:57.184160491 +0100
@@ -1064,7 +1064,7 @@ See
 for possible ways to specify the
 .IR limit .
 .TP
-\fB\-M\fR \fIlimit\fR, \fB\-\-memlimit=\fIlimit\fR, \fB\-\-memory=\fIlimit
+\fB\-M\fR \fIlimit\fR, \fB\-\-memlimit=\fIlimit\fR, (old alias \fB\-\-memory=\fIlimit\fR)
 This is equivalent to specifying
 .BI \-\-memlimit\-compress= limit
 \fB\-\-memlimit\-decompress=\fIlimit\fR.
diff -rupN xz-5.2.9.old/src/xzdec/xzdec.c xz-5.2.9/src/xzdec/xzdec.c
--- xz-5.2.9.old/src/xzdec/xzdec.c	2022-11-24 09:55:48.000000000 +0100
+++ xz-5.2.9/src/xzdec/xzdec.c	2022-12-06 21:35:36.117137979 +0100
@@ -23,7 +23,7 @@
 #include "tuklib_exit.h"
 
 #ifdef TUKLIB_DOSLIKE
-#	include <fcntl.h>
+// #	include <fcntl.h>
 #	include <io.h>
 #endif
 
@@ -65,12 +65,16 @@ help(void)
 "Decompress files in the ." TOOL_FORMAT " format to standard output.\n"
 "\n"
 "  -d, --decompress   (ignored, only decompression is supported)\n"
-"  -k, --keep         (ignored, files are never deleted)\n"
-"  -c, --stdout       (ignored, output is always written to standard output)\n"
 "  -q, --quiet        specify *twice* to suppress errors\n"
-"  -Q, --no-warn      (ignored, the exit status 2 is never used)\n"
 "  -h, --help         display this help and exit\n"
 "  -V, --version      display the version number and exit\n"
+"  -c, --stdout, --to-stdout\n"
+"                     ignored, data are always written to standard output\n"
+"  -d, --decompress, --uncompress\n"
+"                     ignored, only decompression is supported\n"
+"  -k, --keep         ignored, we never create/remove any files\n"
+"  -Q, --no-warn      ignored, we never use exit status 2\n"
+
 "\n"
 "With no FILE, or when FILE is -, read standard input.\n"
 "\n"