Re: rc.d and non daemon servers

[Alistair Crooks <agc%pkgsrc.org@localhost>]

On Wed, Mar 04, 2009 at 09:33:36PM -0500, Steven M. Bellovin wrote:
> On Wed, 4 Mar 2009 16:57:35 -0500
> "Steven M. Bellovin" <smb%cs.columbia.edu@localhost> wrote:
> 
> > On Wed, 4 Mar 2009 15:15:00 -0500
> > Amitai Schlair <schmonz%schmonz.com@localhost> wrote:
> > 
> > > http://libslack.org/daemon/
> > 
> > Interesting, but it's rather, umm, large...  Thanks.  I may still
> > write my own.
> > 
> OK, here it is.  It's dumb and stupid, and does nothing but invoke our
> daemon() subroutine.  If folks care, I'll write a man page and stick it
> into pkgsrc.  Usage should be obvious from the code and daemon(3).

The following changes are taken from the nit department:

        Use a static function for usage message
        Use standard exit values where possible
        Use getopt(3)

and perhaps a license could be placed on the code so that people know
where they stand with it.

Thanks for doing this.

Best wishes,
Alistair

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

static void
usage(const char *prog)
{
        (void) fprintf(stderr, "Usage: %s: [-c] [-f] [-h] command [args]\n", 
prog);
}

int
main(int argc, char *argv[])
{
        int     nochdir;
        int     noclose;
        int     i;

        nochdir = 0;
        noclose = 0;
        while ((i = getopt(argc, argv, "cfh")) != -1) {
                switch(i) {
                case 'c':
                        nochdir = 1;
                        break;
                case 'f':
                        noclose = 1;
                        break;
                case 'h':
                        usage(*argv);
                        exit(EXIT_SUCCESS);
                default:
                        usage(*argv);
                        exit(EXIT_FAILURE);
                }
        }
        if (optind == argc) {
                usage(*argv);
                return 2;
        }
        if (daemon(nochdir, noclose) != 0) {
                perror("daemon");
                return 3;
        }
        execvp(argv[optind], &argv[optind]);
        perror("exec");
        return 4;
}