make all errors return -1; general cleanup/lint; add copyright

SCCS-vsn: usr.bin/mesg/mesg.c 4.4

diff --git a/usr/src/usr.bin/mesg/mesg.c b/usr/src/usr.bin/mesg/mesg.c
index 266937a..fbfcd2b 100644 (file)
--- a/usr/src/usr.bin/mesg/mesg.c
+++ b/usr/src/usr.bin/mesg/mesg.c
@@ -1,4 +1,25 @@
-static char *sccsid = "@(#)mesg.c      4.3 (Berkeley) %G%";
+/*
+ * Copyright (c) 1987 Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that this notice is preserved and that due credit is given
+ * to the University of California at Berkeley. The name of the University
+ * may not be used to endorse or promote products derived from this
+ * software without specific written prior permission. This software
+ * is provided ``as is'' without express or implied warranty.
+ */
+
+#ifndef lint
+char copyright[] =
+"@(#) Copyright (c) 1987 Regents of the University of California.\n\
+ All rights reserved.\n";
+#endif /* not lint */
+
+#ifndef lint
+static char sccsid[] = "@(#)mesg.c     4.4 (Berkeley) %G%";
+#endif /* not lint */
+

 /*
  * mesg -- set current tty to accept or
  *     forbid write permission.
 /*
  * mesg -- set current tty to accept or
  *     forbid write permission.


@@ -8,51 +29,56 @@ static char *sccsid = "@(#)mesg.c    4.3 (Berkeley) %G%";
  *             n forbid messages
  */
 
  *             n forbid messages
  */
 

-#include <stdio.h>

 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <sys/stat.h>

+#include <stdio.h>

 
 

-struct stat sbuf;
-
-char *tty;
-char *ttyname();
+static char *tty;

 
 main(argc, argv)
 
 main(argc, argv)

-char *argv[];
+       int argc;
+       char **argv;

 {
 {

-       int r=0;
-       tty = ttyname(2);
-       if (tty == 0)
-               exit(13);
-       if(stat(tty, &sbuf) < 0) error("cannot stat");
-       if(argc < 2) {
-               if(sbuf.st_mode & 020)
-                       fprintf(stderr,"is y\n");
-               else {  r=1;
-                       fprintf(stderr,"is n\n");
-               }
-       } else  switch(*argv[1]) {
-               case 'y':
-                       newmode(sbuf.st_mode|020); break;
-
-               case 'n':
-                       newmode(sbuf.st_mode&~020); r=1; break;
+       struct stat sbuf;
+       char *ttyname();

 
 

-               default:
-                       error("usage: mesg [y] [n]");
+       if (!(tty = ttyname(2))) {
+               fputs("mesg: not a device in /dev.\n", stderr);
+               exit(-1);
+       }
+       if (stat(tty, &sbuf) < 0) {
+               perror("mesg");
+               exit(-1);
+       }
+       if (argc < 2) {
+               if (sbuf.st_mode & 020) {
+                       fputs("is y\n", stderr);
+                       exit(0);

                }
                }

-       exit(r);
-}
-
-error(s)
-char *s;
-{
-       fprintf(stderr,"mesg: %s\n",s);
-       exit(-1);
+               fputs("is n\n", stderr);
+               exit(1);
+       }
+#define        OTHER_WRITE     020
+       switch(*argv[1]) {
+       case 'y':
+               newmode(sbuf.st_mode | OTHER_WRITE);
+               exit(0);
+       case 'n':
+               newmode(sbuf.st_mode &~ OTHER_WRITE);
+               exit(1);
+       default:
+               fputs("usage: mesg [y] [n]\n", stderr);
+               exit(-1);
+       }
+       /*NOTREACHED*/

 }
 
 }
 

+static

 newmode(m)
 newmode(m)

+       u_short m;

 {
 {

-       if(chmod(tty,m)<0)
-               error("cannot change mode");
+       if (chmod(tty, m) < 0) {
+               perror("mesg");
+               exit(-1);
+       }

 }
 }