1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22/*
23 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27/*	Copyright (c) 1988 AT&T	*/
28/*	  All Rights Reserved  	*/
29
30#pragma ident	"%Z%%M%	%I%	%E% SMI"
31
32#pragma weak _gethz = gethz
33
34#include "lint.h"
35#include <stdio.h>
36#include <ctype.h>
37#include <stdlib.h>
38
39/*
40 *	gethz -- get the value of the clock hertz from the environment.
41 *
42 *	return the clock hertz value if the string "HZ" in the environment is:
43 *		1) Composed entirely of numbers.
44 *		2) Not equal to zero.
45 *	Otherwise 0 is returned.
46 */
47int
48gethz(void)
49{
50	char *sptr, *cptr;
51
52	if ((sptr = getenv("HZ")) == NULL) {
53		return (0);
54	} else {
55		cptr = sptr;
56
57		/* Check that all characters are numeric */
58		while (*cptr) {
59			if (!isdigit((unsigned char)*cptr))
60				return (0);
61			cptr++;
62		}
63		return (atoi(sptr));
64	}
65}
66