From ab855870246c8b10b6ddd9cc7c7aca50a45d92a6 Mon Sep 17 00:00:00 2001
From: "Lee E. McMahon" <lem@research.uucp>
Date: Wed, 10 Jan 1979 15:01:24 -0500
Subject: [PATCH] Research V7 development Work on file usr/src/cmd/comm.c

Synthesized-from: v7
---
 usr/src/cmd/comm.c | 166 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 166 insertions(+)
 create mode 100644 usr/src/cmd/comm.c

diff --git a/usr/src/cmd/comm.c b/usr/src/cmd/comm.c
new file mode 100644
index 0000000000..a137ca3a0e
--- /dev/null
+++ b/usr/src/cmd/comm.c
@@ -0,0 +1,166 @@
+#include <stdio.h>
+#define LB 256
+int	one;
+int	two;
+int	three;
+
+char	*ldr[3];
+
+FILE *ib1;
+FILE *ib2;
+FILE *openfil();
+main(argc,argv)
+char	*argv[];
+{
+	int	l;
+	char	lb1[LB],lb2[LB];
+
+	ldr[0] = "";
+	ldr[1] = "\t";
+	ldr[2] = "\t\t";
+	if(argc > 1)  {
+		if(*argv[1] == '-' && argv[1][1] != 0) {
+			l = 1;
+			while(*++argv[1]) {
+				switch(*argv[1]) {
+				case'1':
+					if(!one) {
+						one = 1;
+						ldr[1][0] =
+						ldr[2][l--] = '\0';
+					}
+					break;
+				case '2':
+					if(!two) {
+						two = 1;
+						ldr[2][l--] = '\0';
+					}
+					break;
+				case '3':
+					three = 1;
+					break;
+				default:
+				fprintf(stderr,"comm: illegal flag\n");
+				exit(1);
+				}
+			}
+			argv++;
+			argc--;
+		}
+	}
+
+	if(argc < 3) {
+		fprintf(stderr,"comm: arg count\n");
+		exit(1);
+	}
+
+	ib1 = openfil(argv[1]);
+	ib2 = openfil(argv[2]);
+
+
+	if(rd(ib1,lb1) < 0) {
+		if(rd(ib2,lb2) < 0)	exit(0);
+		copy(ib2,lb2,2);
+	}
+	if(rd(ib2,lb2) < 0)	copy(ib1,lb1,1);
+
+	while(1) {
+
+		switch(compare(lb1,lb2)) {
+
+			case 0:
+				wr(lb1,3);
+				if(rd(ib1,lb1) < 0) {
+					if(rd(ib2,lb2) < 0)	exit(0);
+					copy(ib2,lb2,2);
+				}
+				if(rd(ib2,lb2) < 0)	copy(ib1,lb1,1);
+				continue;
+
+			case 1:
+				wr(lb1,1);
+				if(rd(ib1,lb1) < 0)	copy(ib2,lb2,2);
+				continue;
+
+			case 2:
+				wr(lb2,2);
+				if(rd(ib2,lb2) < 0)	copy(ib1,lb1,1);
+				continue;
+		}
+	}
+}
+
+rd(file,buf)
+FILE *file;
+char *buf;
+{
+
+	register int i, c;
+	i = 0;
+	while((c = getc(file)) != EOF) {
+		*buf = c;
+		if(c == '\n' || i > LB-2) {
+			*buf = '\0';
+			return(0);
+		}
+		i++;
+		buf++;
+	}
+	return(-1);
+}
+
+wr(str,n)
+	char	*str;
+{
+
+	switch(n) {
+
+		case 1:
+			if(one)	return;
+			break;
+
+		case 2:
+			if(two)	return;
+			break;
+
+		case 3:
+			if(three)	return;
+	}
+	printf("%s%s\n",ldr[n-1],str);
+}
+
+copy(ibuf,lbuf,n)
+FILE *ibuf;
+char *lbuf;
+{
+	do {
+		wr(lbuf,n);
+	} while(rd(ibuf,lbuf) >= 0);
+
+	exit(0);
+}
+
+compare(a,b)
+	char	*a,*b;
+{
+	register char *ra,*rb;
+
+	ra = --a;
+	rb = --b;
+	while(*++ra == *++rb)
+		if(*ra == '\0')	return(0);
+	if(*ra < *rb)	return(1);
+	return(2);
+}
+FILE *openfil(s)
+char *s;
+{
+	FILE *b;
+	if(s[0]=='-' && s[1]==0)
+		b = stdin;
+	else if((b=fopen(s,"r")) == NULL) {
+		fprintf(stderr,"comm: cannot open %s\n",s);
+		exit(1);
+	}
+	return(b);
+}
-- 
2.20.1