--- ray/src/rt/devcomm.c	1989/06/02 17:21:24	1.4
+++ ray/src/rt/devcomm.c	1990/01/08 15:07:31	1.9
@@ -27,7 +27,7 @@ static char SCCSid[] = "$SunId$ LBL";
 #endif
 
 #ifndef WFLUSH
-#define WFLUSH		50		/* flush after this many rays */
+#define WFLUSH		30		/* flush after this many rays */
 #endif
 
 extern char	*getpath(), *getenv();
@@ -39,8 +39,7 @@ int	comm_close(), comm_clear(), comm_paintr(), comm_er
 
 struct driver	comm_driver, comm_default = {
 	comm_close, comm_clear, comm_paintr, comm_getcur,
-	comm_comout, comm_comin,
-	MAXRES, MAXRES, 0
+	comm_comout, comm_comin
 };
 
 FILE	*devin, *devout;
@@ -49,33 +48,28 @@ int	devchild;
 
 
 struct driver *
-comm_init(argv)			/* set up and execute driver */
-char	*argv[];
+comm_init(dname, id)			/* set up and execute driver */
+char	*dname, *id;
 {
 	char	*devname;
 	int	p1[2], p2[2];
-
-	if ((devname = getpath(argv[0], DEVPATH)) == NULL) {
-		stderr_v(argv[0]);
+	char	pin[16], pout[16];
+						/* find driver program */
+	if ((devname = getpath(dname, DEVPATH, 1)) == NULL) {
+		stderr_v(dname);
 		stderr_v(": not found\n");
 		return(NULL);
 	}
+						/* open communication pipes */
 	if (pipe(p1) == -1 || pipe(p2) == -1)
 		goto syserr;
-	if ((devchild = vfork()) == 0) {
+	if ((devchild = vfork()) == 0) {	/* fork driver process */
 		close(p1[1]);
 		close(p2[0]);
-		if (p1[0] != 0) {
-			dup2(p1[0], 0);
-			close(p1[0]);
-		}
-		if (p2[1] != 1) {
-			dup2(p2[1], 1);
-			close(p2[1]);
-		}
-		execv(devname, argv);
-		stderr_v(devname);
-		stderr_v(": cannot execute\n");
+		sprintf(pin, "%d", p1[0]);
+		sprintf(pout, "%d", p2[1]);
+		execl(devname, dname, pin, pout, id, 0);
+		perror(devname);
 		_exit(127);
 	}
 	if (devchild == -1)
@@ -87,13 +81,23 @@ char	*argv[];
 	if ((devin = fdopen(p2[0], "r")) == NULL)
 		goto syserr;
 	bcopy(&comm_default, &comm_driver, sizeof(comm_driver));
+						/* verify & get resolution */
+	putw(COM_SENDM, devout);
+	fflush(devout);
+	if (getw(devin) != COM_RECVM)
+		return(NULL);
+	fread(&comm_driver.pixaspect, sizeof(comm_driver.pixaspect), 1, devin);
+	comm_driver.xsiz = getw(devin);
+	comm_driver.ysiz = getw(devin);
+						/* input handling */
 	signal(SIGIO, onsigio);
-	cmdvec = comm_comout;			/* set error vectors */
+						/* set error vectors */
+	cmdvec = comm_comout;
 	if (wrnvec != NULL)
 		wrnvec = comm_comout;
 	return(&comm_driver);
 syserr:
-	perror(argv[0]);
+	perror(dname);
 	return(NULL);
 }
 
@@ -119,8 +123,8 @@ comm_clear(xres, yres)				/* clear screen */
 int	xres, yres;
 {
 	putc(COM_CLEAR, devout);
-	fwrite(&xres, sizeof(xres), 1, devout);
-	fwrite(&yres, sizeof(yres), 1, devout);
+	putw(xres, devout);
+	putw(yres, devout);
 	fflush(devout);
 }
 
@@ -135,10 +139,10 @@ int	xmin, ymin, xmax, ymax;
 
 	putc(COM_PAINTR, devout);
 	fwrite(col, sizeof(COLOR), 1, devout);
-	fwrite(&xmin, sizeof(xmin), 1, devout);
-	fwrite(&ymin, sizeof(ymin), 1, devout);
-	fwrite(&xmax, sizeof(xmax), 1, devout);
-	fwrite(&ymax, sizeof(ymax), 1, devout);
+	putw(xmin, devout);
+	putw(ymin, devout);
+	putw(xmax, devout);
+	putw(ymax, devout);
 	if (nrays - lastflush >= WFLUSH) {
 		fflush(devout);
 		lastflush = nrays;
@@ -157,8 +161,8 @@ int	*xp, *yp;
 	if (getc(devin) != COM_GETCUR)
 		reply_error("getcur");
 	c = getc(devin);
-	fread(xp, sizeof(*xp), 1, devin);
-	fread(yp, sizeof(*yp), 1, devin);
+	*xp = getw(devin);
+	*yp = getw(devin);
 	return(c);
 }
 
@@ -182,7 +186,8 @@ char	*buf;
 	if (getc(devin) != COM_COMIN)
 		reply_error("comin");
 	mygets(buf, devin);
-	comm_driver.inpready = 0;
+	if (comm_driver.inpready > 0)
+		comm_driver.inpready--;
 }