--- ray/src/hd/rholo4.c	1998/01/04 18:37:11	3.17
+++ ray/src/hd/rholo4.c	1998/10/22 08:47:40	3.21
@@ -1,4 +1,4 @@
-/* Copyright (c) 1997 Silicon Graphics, Inc. */
+/* Copyright (c) 1998 Silicon Graphics, Inc. */
 
 #ifndef lint
 static char SCCSid[] = "$SunId$ SGI";
@@ -16,6 +16,10 @@ static char SCCSid[] = "$SunId$ SGI";
 #define HDSUF	".hdi"
 #endif
 
+#ifndef FNONBLK
+#define FNONBLK		O_NONBLOCK
+#endif
+
 static int	inp_flags;
 static int	dpd[3];
 static FILE	*dpout;
@@ -56,6 +60,12 @@ char	*dname;
 				/* check if outside */
 	if (vdef(OBSTRUCTIONS) && vbool(OBSTRUCTIONS))
 		disp_result(DS_OUTSECT, 0, NULL);
+				/* send eye separation if specified */
+	if (vdef(EYESEP)) {
+		char	fbuf[32];
+		sprintf(fbuf, "%.9e", vflt(EYESEP));
+		disp_result(DS_EYESEP, strlen(fbuf)+1, fbuf);
+	}
 				/* write out hologram grids */
 	for (i = 0; hdlist[i] != NULL; i++)
 		disp_result(DS_ADDHOLO, sizeof(HDGRID), (char *)hdlist[i]);
@@ -99,10 +109,12 @@ int	block;
 		return(2);		/* acceptable failure */
 	}
 	if (msg.nbytes) {		/* get the message body */
+		if (msg.nbytes < 0)
+			error(INTERNAL, "anti-message from display process");
 		buf = (char *)malloc(msg.nbytes);
 		if (buf == NULL)
 			error(SYSTEM, "out of memory in disp_check");
-		if (fcntl(dpd[0], F_SETFL, inp_flags=0) < 0)
+		if (inp_flags != 0 && fcntl(dpd[0], F_SETFL, inp_flags=0) < 0)
 			goto fcntlerr;
 		if (readbuf(dpd[0], buf, msg.nbytes) != msg.nbytes)
 			goto readerr;
@@ -116,12 +128,17 @@ int	block;
 	case DR_NEWSET:		/* new calculation set */
 		if (msg.nbytes % sizeof(PACKHEAD))
 			error(INTERNAL, "bad DR_NEWSET from display process");
-		disp_result(DS_STARTIMM, 0, NULL);
+		if (msg.nbytes)
+			disp_result(DS_STARTIMM, 0, NULL);
 		bundle_set(BS_NEW, (PACKHEAD *)buf, msg.nbytes/sizeof(PACKHEAD));
-		disp_result(DS_ENDIMM, 0, NULL);
-		disp_flush();
+		if (msg.nbytes) {
+			disp_result(DS_ENDIMM, 0, NULL);
+			disp_flush();
+		}
 		break;
 	case DR_ADDSET:		/* add to calculation set */
+		if (!msg.nbytes)
+			break;
 		if (msg.nbytes % sizeof(PACKHEAD))
 			error(INTERNAL, "bad DR_ADDSET from display process");
 		disp_result(DS_STARTIMM, 0, NULL);
@@ -130,6 +147,8 @@ int	block;
 		disp_flush();
 		break;
 	case DR_ADJSET:		/* adjust calculation set members */
+		if (!msg.nbytes)
+			break;
 		if (msg.nbytes % sizeof(PACKHEAD))
 			error(INTERNAL, "bad DR_ADJSET from display process");
 		disp_result(DS_STARTIMM, 0, NULL);
@@ -138,6 +157,8 @@ int	block;
 		disp_flush();
 		break;
 	case DR_DELSET:		/* delete from calculation set */
+		if (!msg.nbytes)
+			break;
 		if (msg.nbytes % sizeof(PACKHEAD))
 			error(INTERNAL, "bad DR_DELSET from display process");
 		bundle_set(BS_DEL, (PACKHEAD *)buf, msg.nbytes/sizeof(PACKHEAD));
@@ -214,7 +235,11 @@ int	type, nbytes;
 char	*p;
 {
 	MSGHEAD	msg;
-
+					/* consistency checks */
+#ifdef DEBUG
+	if (nbytes < 0 || nbytes > 0 & p == NULL)
+		error(CONSISTENCY, "bad buffer handed to disp_result");
+#endif
 	if (dpout == NULL)
 		return;
 	msg.type = type;