--- ray/src/px/pfilt.c	2003/06/30 14:59:12	2.25
+++ ray/src/px/pfilt.c	2018/07/26 23:50:40	2.32
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char RCSid[] = "$Id: pfilt.c,v 2.25 2003/06/30 14:59:12 schorsch Exp $";
+static const char RCSid[] = "$Id: pfilt.c,v 2.32 2018/07/26 23:50:40 greg Exp $";
 #endif
 /*
  *  pfilt.c - program to post-process picture file.
@@ -13,13 +13,14 @@ static const char RCSid[] = "$Id: pfilt.c,v 2.25 2003/
 #include  <signal.h>
 #include  <string.h>
 
-#include  "standard.h"
 #include  "platform.h"
+#include  "standard.h"
+#include  "rtio.h"
 #include  "color.h"
 #include  "view.h"
 #include  "paths.h"
+#include  "pfilt.h"
 
-extern float  *matchlamp();
 
 #define	 FEQ(a,b)	((a) >= .98*(b) && (a) <= 1.02*(b))
 
@@ -83,12 +84,23 @@ int  orad = 0;			/* output window radius */
 
 char  *progname;
 
+static gethfunc headline;
+static brightfunc_t rgb_bright;
+static brightfunc_t xyz_bright;
+static void copyfile(FILE  *in, FILE  *out);
+static void pass1(FILE  *in);
+static void pass2(FILE  *in);
+static void scan2init(void);
+static void scan2sync(int  r);
+static void scan2flush(void);
 
-main(argc, argv)
-int  argc;
-char  **argv;
+
+int
+main(
+	int  argc,
+	char  **argv
+)
 {
-	extern int  headline();
 	FILE  *fin;
 	float  *lampcolor;
 	char  *lamptype = NULL;
@@ -306,31 +318,35 @@ char  **argv;
 	pass2(fin);
 
 	quit(estatus);
+	return estatus; /* pro forma return */
 }
 
 
-double
-rgb_bright(clr)
-COLOR  clr;
+static double
+rgb_bright(
+	COLOR  clr
+)
 {
 	return(bright(clr));
 }
 
 
-double
-xyz_bright(clr)
-COLOR  clr;
+static double
+xyz_bright(
+	COLOR  clr
+)
 {
 	return(clr[CIEY]);
 }
 
 
-double	(*ourbright)() = rgb_bright;
+brightfunc_t *ourbright = rgb_bright;
 
-
-int
-headline(s)				/* process line from header */
-char  *s;
+static int
+headline(				/* process line from header */
+	char	*s,
+	void	*p
+)
 {
 	char  fmt[32];
 
@@ -353,10 +369,13 @@ char  *s;
 }
 
 
-copyfile(in, out)			/* copy a file */
-register FILE  *in, *out;
+static void
+copyfile(			/* copy a file */
+	FILE  *in,
+	FILE  *out
+)
 {
-	register int  c;
+	int  c;
 
 	while ((c = getc(in)) != EOF)
 		putc(c, out);
@@ -368,8 +387,10 @@ register FILE  *in, *out;
 }
 
 
-pass1(in)				/* first pass of picture file */
-FILE  *in;
+static void
+pass1(				/* first pass of picture file */
+	FILE  *in
+)
 {
 	int  i;
 	COLOR  *scan;
@@ -401,8 +422,10 @@ FILE  *in;
 }
 
 
-pass2(in)			/* last pass on file, write to stdout */
-FILE  *in;
+static void
+pass2(			/* last pass on file, write to stdout */
+	FILE  *in
+)
 {
 	int  yread;
 	int  ycent, xcent;
@@ -452,11 +475,12 @@ FILE  *in;
 }
 
 
-scan2init()			/* prepare scanline arrays */
+static void
+scan2init(void)			/* prepare scanline arrays */
 {
 	COLOR	ctmp;
 	double	d;
-	register int  i;
+	int  i;
 
 	xbrad = xres/ncols/2 + 1;
 	ybrad = yres/nrows/2 + 1;
@@ -490,12 +514,12 @@ scan2init()			/* prepare scanline arrays */
 	if (obarsize > 0) {
 		scoutbar = (COLOR **)malloc(obarsize*sizeof(COLOR *));
 		greybar = (float **)malloc(obarsize*sizeof(float *));
-		if (scoutbar == NULL | greybar == NULL)
+		if ((scoutbar == NULL) | (greybar == NULL))
 			goto memerr;
 		for (i = 0; i < obarsize; i++) {
 			scoutbar[i] = (COLOR *)malloc(ncols*sizeof(COLOR));
 			greybar[i] = (float *)malloc(ncols*sizeof(float));
-			if (scoutbar[i] == NULL | greybar[i] == NULL)
+			if ((scoutbar[i] == NULL) | (greybar[i] == NULL))
 				goto memerr;
 		}
 	} else {
@@ -529,13 +553,15 @@ memerr:
 }
 
 
-scan2sync(r)			/* synchronize grey averages and output scan */
-int  r;
+static void
+scan2sync(			/* synchronize grey averages and output scan */
+	int  r
+)
 {
 	static int  nextrow = 0;
 	COLOR  ctmp;
 	int  ybot;
-	register int  c;
+	int  c;
 					/* average input scanlines */
 	while (nextrow <= r+orad && nextrow < nrows) {
 		ybot = (nextrow+.5)*yres/nrows;
@@ -555,9 +581,10 @@ int  r;
 }
 
 
-scan2flush()			/* flush output buffer */
+static void
+scan2flush(void)			/* flush output buffer */
 {
-	register int  r;
+	int  r;
 
 	for (r = nrows-orad; r < nrows; r++)
 		if (fwritescan(scoutbar[r%obarsize], ncols, stdout) < 0)