diff --git a/Files b/Files
index 919d50808..8c3a948d0 100644
--- a/Files
+++ b/Files
@@ -12,13 +12,13 @@ dat:
 (files for all versions)
 Arch.des        Barb.des        Caveman.des     Healer.des      Knight.des
 Monk.des        Priest.des      Ranger.des      Rogue.des       Samurai.des
-Tourist.des     Valkyrie.des    Wizard.des      bigroom.des     castle.des
-cmdhelp         data.base       dungeon.def     endgame.des     gehennom.des
-help            hh              history         knox.des        license
-medusa.des      mines.des       opthelp         oracle.des      oracles.txt
-quest.txt       rumors.fal      rumors.tru      sokoban.des     symbols
-tower.des       wizhelp         yendor.des      tribute         bogusmon.txt
-engrave.txt     epitaph.txt
+Tourist.des     Valkyrie.des    Wizard.des      bigroom.des     bogusmon.txt
+castle.des      cmdhelp         data.base       dungeon.def     endgame.des
+engrave.txt     epitaph.txt     gehennom.des    help            hh
+history         keyhelp         knox.des        license         medusa.des
+mines.des       opthelp         oracle.des      oracles.txt     quest.txt
+rumors.fal      rumors.tru      sokoban.des     symbols         tower.des
+tribute         wizhelp         yendor.des
 
 doc:
 (files for all versions)
diff --git a/dat/keyhelp b/dat/keyhelp
new file mode 100644
index 000000000..41ab37ef1
--- /dev/null
+++ b/dat/keyhelp
@@ -0,0 +1,58 @@
+	Depending upon hardware or operating system or NetHack's interface,
+	some keystrokes may be off-limits.
+
+	For example, ^S and ^Q are often used for XON/XOFF flow-control,
+	meaning that ^S suspends output and subsequent ^Q resumes suspended
+	output.  When that it the case, neither of those characters will
+	reach NetHack when it is waiting for a command keystroke.  So they
+	aren't used as commands, but 'whatdoes' might not be able to tell
+	you that if they don't get passed through to NetHack.
+
+	^M or <return> or <enter> is likely to be transformed into ^J or
+	<linefeed> or 'newline' before being passed to NetHack for handling.
+	So it isn't used as a command, and 'whatdoes' might seem as if it
+	is reporting the wrong character but will be operating correctly if
+	it describes ^J when you type ^M.
+
+	A NUL character, typed as ^<space> on some keyboards, ^@ on others,
+	and maybe not typeable at all on yet others.  It is not used as a
+	command, and will be converted into ESC before reaching 'whatdoes'.
+	Unlike ^M, this transformation is performed by NetHack itself.
+	But like ^M, if you type NUL and get feedback about ESC, the
+	situation is expected.
+
+	ESC itself is a synonym for ^[, and is another source of oddity.
+	Various function keys, including cursor arrow keys, may transmit
+	an "escape sequence" of ESC + [ + other stuff, confusing NetHack
+	as to what command was intended since the ESC will be processed
+	and then whatever follows will seem to NetHack like--and be used
+	as--something typed by the user.  (If you press a function key and
+	a menu of the armor your hero is wearing appears, what happened
+	was that an escape sequence was sent to NetHack, its ESC aborted
+	any pending key operation, its '[' was then treated as a command
+	to show worn armor, and the "other stuff" probably got silently
+	discarded as invalid choices while you dismissed the menu.)
+
+	If you have NetHack's 'altmeta' option enabled, meaning that the
+	<alt> or <option> key, when used as shift while typing some other
+	character, transmits ESC and then the other character so NetHack
+	should treat that other character as a meta-character, then ESC
+	takes on added potential for confusion.  Implicit in the handling
+	of a two character sequence ESC + something is the fact that when
+	NetHack sees ESC, it needs to wait for another character before
+	it can decide what to do.  So if you type ESC manually, you'll
+	need to type it a second time or NetHack will sit there waiting.
+	(It will then be treated as if you typed ESC rather than M-ESC.)
+
+	On some systems, typing ^\ will send a QUIT signal to the current
+	process, probably killing it and possibly causing it to save a
+	core dump.  It is not used for any NetHack command, so don't type
+	that character.
+
+	One last note:  characters shown as ^x mean that you should hold
+	down the <control> or <ctrl> key as a shift and then type 'x'.
+	Control characters are all implicitly uppercase, but you don't
+	need to press the shift key while typing them.  The opposite is
+	true for meta-characters:  they can be either case, so you need
+	to use shift as well as <meta> or <alt> to generate an uppercase
+	letter meta-character.
diff --git a/include/global.h b/include/global.h
index 0a4c76ac5..4a6647243 100644
--- a/include/global.h
+++ b/include/global.h
@@ -1,4 +1,4 @@
-/* NetHack 3.6	global.h	$NHDT-Date: 1450306170 2015/12/16 22:49:30 $  $NHDT-Branch: NetHack-3.6.0 $:$NHDT-Revision: 1.47 $ */
+/* NetHack 3.6	global.h	$NHDT-Date: 1465114189 2016/06/05 08:09:49 $  $NHDT-Branch: NetHack-3.6.0 $:$NHDT-Revision: 1.49 $ */
 /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
 /* NetHack may be freely redistributed.  See license for details. */
 
@@ -18,6 +18,7 @@
 #define RECORD "record"         /* file containing list of topscorers */
 #define HELP "help"             /* file containing command descriptions */
 #define SHELP "hh"              /* abbreviated form of the same */
+#define KEYHELP "keyhelp"       /* explanatory text for 'whatdoes' command */
 #define DEBUGHELP "wizhelp"     /* file containing debug mode cmds */
 #define RUMORFILE "rumors"      /* file with fortune cookies */
 #define ORACLEFILE "oracles"    /* file with oracular information */
diff --git a/src/pager.c b/src/pager.c
index 77ade35b0..b35601f9e 100644
--- a/src/pager.c
+++ b/src/pager.c
@@ -1,4 +1,4 @@
-/* NetHack 3.6	pager.c	$NHDT-Date: 1463790247 2016/05/21 00:24:07 $  $NHDT-Branch: NetHack-3.6.0 $:$NHDT-Revision: 1.98 $ */
+/* NetHack 3.6	pager.c	$NHDT-Date: 1465114189 2016/06/05 08:09:49 $  $NHDT-Branch: NetHack-3.6.0 $:$NHDT-Revision: 1.107 $ */
 /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
 /* NetHack may be freely redistributed.  See license for details. */
 
@@ -1306,6 +1306,32 @@ doidtrap()
     return 0;
 }
 
+STATIC_DCL void
+dowhatdoes_help()
+{
+    dlb *fp;
+    char *p, buf[BUFSZ];
+    winid tmpwin = create_nhwindow(NHW_TEXT);
+
+    fp = dlb_fopen(KEYHELP, "r");
+    if (!fp) {
+        pline("Cannot open \"%s\" data file!", KEYHELP);
+        display_nhwindow(WIN_MESSAGE, TRUE);
+        return;
+    }
+    while (dlb_fgets(buf, (int) sizeof buf, fp)) {
+        if (*buf == '#')
+            continue;
+        for (p = buf; *p; p++)
+            if (*p != ' ' && *p != '\t')
+                break;
+        putstr(tmpwin, 0, p);
+    }
+    (void) dlb_fclose(fp);
+    display_nhwindow(tmpwin, TRUE);
+    destroy_nhwindow(tmpwin);
+}
+
 char *
 dowhatdoes_core(q, cbuf)
 char q;
@@ -1317,7 +1343,7 @@ char *cbuf;
 
     fp = dlb_fopen(CMDHELPFILE, "r");
     if (!fp) {
-        pline("Cannot open data file!");
+        pline("Cannot open \"%s\" data file!", CMDHELPFILE);
         return 0;
     }
 
@@ -1353,21 +1379,40 @@ char *cbuf;
 int
 dowhatdoes()
 {
+    static boolean once = FALSE;
     char bufr[BUFSZ];
     char q, *reslt;
 
+    if (!once) {
+        pline("Ask about '&' or '?' to get more info.%s",
+              iflags.altmeta ? "  (For ESC, type it twice.)" : "");
+        once = TRUE;
+    }
 #if defined(UNIX) || defined(VMS)
-    introff();
+    introff(); /* disables ^C but not ^\ */
 #endif
     q = yn_function("What command?", (char *) 0, '\0');
+    if (q == '\033' && iflags.altmeta) {
+        /* in an ideal world, we would know whether another keystroke
+           was already pending, but this is not an ideal world...
+           if user types ESC, we'll essentially hang until another
+           character is typed */
+        q = yn_function("", (char *) 0, '\0');
+        if (q != '\033')
+            q = (char) ((uchar) q | 0200);
+    }
 #if defined(UNIX) || defined(VMS)
-    intron();
+    intron(); /* reenables ^C */
 #endif
     reslt = dowhatdoes_core(q, bufr);
-    if (reslt)
-        pline1(reslt);
-    else
-        pline("I've never heard of such commands.");
+    if (reslt) {
+        if (q == '&' || q == '?')
+            dowhatdoes_help();
+        pline("%s", reslt);
+    } else {
+        pline("No such command '%s', char code %d (0%03o or 0x%02x).",
+              visctrl(q), (uchar) q, (uchar) q, (uchar) q);
+    }
     return 0;
 }
 
diff --git a/sys/unix/Makefile.top b/sys/unix/Makefile.top
index 88907a786..88dc3b878 100644
--- a/sys/unix/Makefile.top
+++ b/sys/unix/Makefile.top
@@ -1,5 +1,5 @@
 #	NetHack Makefile.
-# NetHack 3.6  Makefile.top	$NHDT-Date: 1449621572 2015/12/09 00:39:32 $  $NHDT-Branch: NetHack-3.6.0 $:$NHDT-Revision: 1.33 $
+# NetHack 3.6  Makefile.top	$NHDT-Date: 1465114189 2016/06/05 08:09:49 $  $NHDT-Branch: NetHack-3.6.0 $:$NHDT-Revision: 1.35 $
 
 # Root of source tree:
 NHSROOT=.
@@ -76,7 +76,7 @@ VARDAT = $(VARDATD) $(VARDATND)
 # end of configuration
 #
 
-DATHELP = help hh cmdhelp history opthelp wizhelp
+DATHELP = help hh cmdhelp keyhelp history opthelp wizhelp
 
 SPEC_LEVS = asmodeus.lev baalz.lev bigrm-*.lev castle.lev fakewiz?.lev \
 	juiblex.lev knox.lev medusa-?.lev minend-?.lev minefill.lev \