detach.c

早期freebsd实现

#ifndef lint
static char sccsid[] = 	"@(#)detach.c	2.2 88/08/10 4.0 RPCSRC";
#endif
/*
 * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
 * unrestricted use provided that this legend is included on all tape
 * media and as a part of the software program in whole or part.  Users
 * may copy or modify Sun RPC without charge, but are not authorized
 * to license or distribute it to anyone else except as part of a product or
 * program developed by the user.
 * 
 * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
 * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
 * 
 * Sun RPC is provided with no support and without any obligation on the
 * part of Sun Microsystems, Inc. to assist in its use, correction,
 * modification or enhancement.
 * 
 * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
 * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
 * OR ANY PART THEREOF.
 * 
 * In no event will Sun Microsystems, Inc. be liable for any lost revenue
 * or profits or other special, indirect and consequential damages, even if
 * Sun has been advised of the possibility of such damages.
 * 
 * Sun Microsystems, Inc.
 * 2550 Garcia Avenue
 * Mountain View, California  94043
 */

/*
 * Copyright (C) 1986, Sun Microsystems, Inc.
 */

#include <sys/ioctl.h>
#include <fcntl.h>

/*
 * detach from tty
 */
detachfromtty()
{
	int tt;

	close(0);
	close(1);
	close(2);
	switch (fork()) {
	case -1:
		perror("fork");
		break;
	case 0:
		break;
	default:
		exit(0);
	}
	tt = open("/dev/tty", O_RDWR);
	if (tt > 0) {
		ioctl(tt, TIOCNOTTY, 0);
		close(tt);
	}
	(void)open("/dev/null", O_RDWR, 0);
	dup(0);
	dup(0);
}