Many places in the code NULL is used in integer context, where

plain 0 should be used.  This happens to work because we #define
NULL to 0, but is stylistically wrong and can cause problems
for people trying to port bits of code to other environments.

PR:		2752
Submitted by:	Arne Henrik Juul <arnej@imf.unit.no>

3 files changed, 17 insertions, 17 deletions

diff --git a/games/cribbage/io.c b/games/cribbage/io.c
index c38c119..b4c2f15 100644
--- a/games/cribbage/io.c
+++ b/games/cribbage/io.c
@@ -250,10 +250,10 @@ incard(crd)
 	if (!(line = getline()))
 		goto gotit;
 	p = p1 = line;
-	while (*p1 != ' ' && *p1 != NULL)
+	while (*p1 != ' ' && *p1 != '\0')
 		++p1;
-	*p1++ = NULL;
-	if (*p == NULL)
+	*p1++ = '\0';
+	if (*p == '\0')
 		goto gotit;
 
 	/* IMPORTANT: no real card has 2 char first name */
@@ -289,17 +289,17 @@ incard(crd)
 	if (rnk == EMPTY)
 		goto gotit;
 	p = p1;
-	while (*p1 != ' ' && *p1 != NULL)
+	while (*p1 != ' ' && *p1 != '\0')
 		++p1;
-	*p1++ = NULL;
-	if (*p == NULL)
+	*p1++ = '\0';
+	if (*p == '\0')
 		goto gotit;
 	if (!strcmp("OF", p)) {
 		p = p1;
-		while (*p1 != ' ' && *p1 != NULL)
+		while (*p1 != ' ' && *p1 != '\0')
 			++p1;
-		*p1++ = NULL;
-		if (*p == NULL)
+		*p1++ = '\0';
+		if (*p == '\0')
 			goto gotit;
 	}
 	sut = EMPTY;
@@ -348,7 +348,7 @@ number(lo, hi, prompt)
 
 	for (sum = 0;;) {
 		msg(prompt);
-		if (!(p = getline()) || *p == NULL) {
+		if (!(p = getline()) || *p == '\0') {
 			msg(quiet ? "Not a number" :
 			    "That doesn't look like a number");
 			continue;
@@ -363,7 +363,7 @@ number(lo, hi, prompt)
 				++p;
 			}
 
-		if (*p != ' ' && *p != '\t' && *p != NULL)
+		if (*p != ' ' && *p != '\t' && *p != '\0')
 			sum = lo - 1;
 		if (sum >= lo && sum <= hi)
 			break;
diff --git a/games/cribbage/score.c b/games/cribbage/score.c
index 239e26d..ecfed9a 100644
--- a/games/cribbage/score.c
+++ b/games/cribbage/score.c
@@ -115,7 +115,7 @@ scorehand(hand, starter, n, crb, do_explain)
 	CARD h[(CINHAND + 1)];
 	char buf[32];
 
-	expl[0] = NULL;		/* initialize explanation */
+	expl[0] = '\0';		/* initialize explanation */
 	score = 0;
 	flag = TRUE;
 	k = hand[0].suit;
@@ -131,7 +131,7 @@ scorehand(hand, starter, n, crb, do_explain)
 	}
 
 	if (flag && n >= CINHAND) {
-		if (do_explain && expl[0] != NULL)
+		if (do_explain && expl[0] != '\0')
 			strcat(expl, ", ");
 		if (starter.suit == k) {
 			score += 5;
@@ -140,13 +140,13 @@ scorehand(hand, starter, n, crb, do_explain)
 		} else
 			if (!crb) {
 				score += 4;
-				if (do_explain && expl[0] != NULL)
+				if (do_explain && expl[0] != '\0')
 					strcat(expl, ", Four-flush");
 				else
 					strcpy(expl, "Four-flush");
 			}
 	}
-	if (do_explain && expl[0] != NULL)
+	if (do_explain && expl[0] != '\0')
 		strcat(expl, ", ");
 	h[n] = starter;
 	sorthand(h, n + 1);	/* sort by rank */
diff --git a/games/rogue/inventory.c b/games/rogue/inventory.c
index 8fa88a8..5dd6f3d 100644
--- a/games/rogue/inventory.c
+++ b/games/rogue/inventory.c
@@ -176,9 +176,9 @@ struct id_com_s com_id_tab[COMS] = {
 	'b',	"b       down & left",
 	'c',	"c       call object",
 	'n',	"n       down & right",
-	NULL,	"<SHIFT><dir>: run that way",
+	'\0',	"<SHIFT><dir>: run that way",
 	')',	")       print current weapon",
-	NULL,	"<CTRL><dir>: run till adjacent",
+	'\0',	"<CTRL><dir>: run till adjacent",
 	']',	"]       print current armor",
 	'f',	"f<dir>  fight till death or near death",
 	'=',	"=       print current rings",