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Re: /bin/hostname options/arguments

From: Przemyslaw Nowaczyk (p_nowaczyko2.pl)
Date: Thu Mar 09 2006 - 11:53:11 CST


On Thu, Mar 09, 2006 at 10:57:47AM +0100, Przemyslaw Nowaczyk wrote:
> hi,
> I've got a question about hostname arguments.. the hostname(1) says:
> "hostname - set *or* print name of current host system" so as I understand it
> something like: 'hostname -s new_name' shouldn't be allowed right? becouse we
> acctually don't know what to do (set or print, assuming we're running root)..
> if I'm right - here's a diff to change that behavior (with some KNF fixups)..
> if not - sorry for spamming..
>
> <snip>
>
> and one more thing.. if I'm right, shouldn't the usage args look like
> usage: hostname [-s | name-of-host]?
>

here're all the changes (to man page too).. could somebody verify if my idea
is right..?

Index: hostname.1
===================================================================
RCS file: /cvs/src/bin/hostname/hostname.1,v
retrieving revision 1.18
diff -u -r1.18 hostname.1
--- hostname.1 2003/12/03 14:06:08 1.18
+++ hostname.1 2006/03/09 17:49:16
-38,8 +38,7
 .Nd set or print name of current host system
 .Sh SYNOPSIS
 .Nm hostname
-.Op Fl s
-.Op Ar name-of-host
+.Op Fl s | Ar name-of-host
 .Sh DESCRIPTION
 The
 .Nm
Index: hostname.c
===================================================================
RCS file: /cvs/src/bin/hostname/hostname.c,v
retrieving revision 1.7
diff -u -r1.7 hostname.c
--- hostname.c 2003/06/02 23:32:08 1.7
+++ hostname.c 2006/03/09 17:49:16
-52,15 +52,13
 #include <string.h>
 #include <unistd.h>
 
-extern char *__progname;
+__dead void usage(void);
 
-void usage(void);
-
 int
 main(int argc, char *argv[])
 {
- int ch, sflag;
- char *p, hostname[MAXHOSTNAMELEN];
+ int ch, sflag;
+ char *p, hostname[MAXHOSTNAMELEN];
 
         sflag = 0;
         while ((ch = getopt(argc, argv, "s")) != -1)
-70,6 +68,7
                         break;
                 default:
                         usage();
+ /* NOTREACHED */
                 }
         argc -= optind;
         argv += optind;
-78,6 +77,8
                 usage();
 
         if (*argv) {
+ if (sflag)
+ usage();
                 if (sethostname(*argv, strlen(*argv)))
                         err(1, "sethostname");
         } else {
-90,9 +91,11
         exit(0);
 }
 
-void
+__dead void
 usage(void)
 {
- (void)fprintf(stderr, "usage: %s [-s] [name-of-host]\n", __progname);
+ extern char *__progname;
+
+ (void)fprintf(stderr, "usage: %s [-s | name-of-host]\n", __progname);
         exit(1);
 }

--
Przemyslaw Nowaczyk <p_nowaczyko2.pl>
CS student Poznan University of Technology