"fix" #H894 - reading mail violates illiterate conduct (trunk only)

     From a bug report, reading a scroll
of mail violates illiterate conduct and he requests that it not do so.
I didn't go that far, since unlike needing to read the Book of the Dead
to be able to finish the game, reading scrolls of mail is completely
voluntary and someone attempting voluntary challanges can choose not to
do it.  Instead, this issues a prompt to require confirmation if reading
such a scroll will be the first violation of that conduct.  Ordinary
players can answer no and then use '!' to read mail from a shell.  I'm not
sure what'll happen to players on public servers who aren't given access
to a shell.  Usually they wouldn't be able to get mail either, so more
elaborate servers like the one at nethack.alt.org which allow players to
use mail to communicate with each other will have to come up with their
own solution (perhaps by providing a mail-reader-only shell).

doc/fixes35.0

@@ -255,6 +255,8 @@ wizard mode: WIZKIT wishes could overflow inventory's 52 slots
 when loading bones files, censor suspect characters from player-supplied
 	strings such as pet and fruit names
 can't swap places with tame grid bug when moving diagonally
+require confirmation to read a scroll of mail if doing so will be the first
+	violation of illiteracy conduct
 
 
 Platform- and/or Interface-Specific Fixes

src/read.c

@@ -1,4 +1,4 @@
-/*	SCCS Id: @(#)read.c	3.5	2007/04/07	*/
+/*	SCCS Id: @(#)read.c	3.5	2007/07/13	*/
 /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
 /* NetHack may be freely redistributed.  See license for details. */
 
@@ -124,16 +124,31 @@ doread()
 	    }
 	}
 
+	confused = (Confusion != 0);
+#ifdef MAIL
+	if (scroll->otyp == SCR_MAIL) {
+	    confused = FALSE;	/* override */
+	    /* reading mail is a convenience for the player and takes
+	       place outside the game, so shouldn't affect gameplay;
+	       on the other hand, it starts by explicitly making the
+	       hero actively read something, which is pretty hard
+	       to simply ignore; as a compromise, if the player has
+	       maintained illiterate conduct so far, and this mail
+	       scroll didn't come from bones, ask for confirmation */
+	    if (!u.uconduct.literate) {
+		if (!scroll->spe &&
+	  yn("Reading mail will violate \"illiterate\" conduct.  Read anyway?")
+		    != 'y') return 0;
+	    }
+	}
+#endif
+
 	/* Actions required to win the game aren't counted towards conduct */
 	if (scroll->otyp != SPE_BOOK_OF_THE_DEAD &&
 		scroll->otyp != SPE_BLANK_PAPER &&
 		scroll->otyp != SCR_BLANK_PAPER)
 	    u.uconduct.literate++;
 
-	confused = (Confusion != 0);
-#ifdef MAIL
-	if (scroll->otyp == SCR_MAIL) confused = FALSE;
-#endif
 	if(scroll->oclass == SPBOOK_CLASS) {
 	    return(study_book(scroll));
 	}