OpenSolaris Launch

1 files changed, 84 insertions, 0 deletions

diff --git a/usr/src/lib/libcurses/screen/napms.c b/usr/src/lib/libcurses/screen/napms.c
new file mode 100644
index 0000000000..2f98e23076
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+++ b/usr/src/lib/libcurses/screen/napms.c
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+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License, Version 1.0 only
+ * (the "License").  You may not use this file except in compliance
+ * with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+/*
+ * Copyright 1997 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+/*	Copyright (c) 1988 AT&T	*/
+/*	  All Rights Reserved	*/
+
+/*
+ * University Copyright- Copyright (c) 1982, 1986, 1988
+ * The Regents of the University of California
+ * All Rights Reserved
+ *
+ * University Acknowledgment- Portions of this document are derived from
+ * software developed by the University of California, Berkeley, and its
+ * contributors.
+ */
+
+#pragma ident	"%Z%%M%	%I%	%E% SMI"
+
+/*LINTLIBRARY*/
+
+#include	"curses_inc.h"
+#include	<stdio.h>
+#include	<sys/types.h>
+#include	<poll.h>
+
+/*
+ * napms.  Sleep for ms milliseconds.  We don't expect a particularly good
+ * resolution - 60ths of a second is normal, 10ths might even be good enough,
+ * but the rest of the program thinks in ms because the unit of resolution
+ * varies from system to system.  (In some countries, it's 50ths, for example.)
+ * Vaxen running 4.2BSD and 3B's use 100ths.
+ *
+ * Here are some reasonable ways to get a good nap.
+ *
+ * (1) Use the poll() or select() system calls in SVr3 or Berkeley 4.2BSD.
+ *
+ * (2) Use the 1/10th second resolution wait in the System V tty driver.
+ *     It turns out this is hard to do - you need a tty line that is
+ *     always unused that you have read permission on to sleep on.
+ *
+ * (3) Install the ft (fast timer) device in your kernel.
+ *     This is a psuedo-device to which an ioctl will wait n ticks
+ *     and then send you an alarm.
+ *
+ * (4) Install the nap system call in your kernel.
+ *     This system call does a timeout for the requested number of ticks.
+ *
+ * (5) Write a routine that busy waits checking the time with ftime.
+ *     Ftime is not present on SYSV systems, and since this busy waits,
+ *     it will drag down response on your system.  But it works.
+ */
+
+int
+napms(int ms)
+{
+	struct pollfd pollfd;
+
+	if (poll(&pollfd, 0L, ms) == -1)
+		perror("poll");
+	return (OK);
+}