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sleep.c revision 1.21 
      1 /* $NetBSD: sleep.c,v 1.21 2007/08/18 00:41:52 hubertf Exp $ */
      2 
      3 /*
      4  * Copyright (c) 1988, 1993, 1994
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. Neither the name of the University nor the names of its contributors
     16  *    may be used to endorse or promote products derived from this software
     17  *    without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  * SUCH DAMAGE.
     30  */
     31 
     32 #include <sys/cdefs.h>
     33 #ifndef lint
     34 __COPYRIGHT("@(#) Copyright (c) 1988, 1993, 1994\n\
     35 	The Regents of the University of California.  All rights reserved.\n");
     36 #endif /* not lint */
     37 
     38 #ifndef lint
     39 #if 0
     40 static char sccsid[] = "@(#)sleep.c	8.3 (Berkeley) 4/2/94";
     41 #else
     42 __RCSID("$NetBSD: sleep.c,v 1.21 2007/08/18 00:41:52 hubertf Exp $");
     43 #endif
     44 #endif /* not lint */
     45 
     46 #include <ctype.h>
     47 #include <err.h>
     48 #include <locale.h>
     49 #include <math.h>
     50 #include <signal.h>
     51 #include <stdio.h>
     52 #include <stdlib.h>
     53 #include <time.h>
     54 #include <unistd.h>
     55 
     56 static void alarmhandle(int);
     57 static void usage(void);
     58 int main(int, char *[]);
     59 
     60 int
     61 main(int argc, char *argv[])
     62 {
     63 	char *arg, *temp;
     64 	double fval, ival, val;
     65 	struct timespec ntime;
     66 	int ch, fracflag;
     67 
     68 	setprogname(argv[0]);
     69 	(void)setlocale(LC_ALL, "");
     70 
     71 	(void)signal(SIGALRM, alarmhandle);
     72 
     73 	while ((ch = getopt(argc, argv, "")) != -1)
     74 		switch(ch) {
     75 		default:
     76 			usage();
     77 		}
     78 	argc -= optind;
     79 	argv += optind;
     80 
     81 	if (argc != 1)
     82 		usage();
     83 
     84 	/*
     85 	 * Okay, why not just use atof for everything? Why bother
     86 	 * checking if there is a fraction in use? Because the old
     87 	 * sleep handled the full range of integers, that's why, and a
     88 	 * double can't handle a large long. This is fairly useless
     89 	 * given how large a number a double can hold on most
     90 	 * machines, but now we won't ever have trouble. If you want
     91 	 * 1000000000.9 seconds of sleep, well, that's your
     92 	 * problem. Why use an isdigit() check instead of checking for
     93 	 * a period? Because doing it this way means locales will be
     94 	 * handled transparently by the atof code.
     95 	 */
     96 	fracflag = 0;
     97 	arg = *argv;
     98 	for (temp = arg; *temp != '\0'; temp++)
     99 		if (!isdigit((unsigned char)*temp))
    100 			fracflag++;
    101 
    102 	if (fracflag) {
    103 		val = atof(arg);
    104 		if (val <= 0)
    105 			usage();
    106 		ival = floor(val);
    107 		fval = (1000000000 * (val-ival));
    108 		ntime.tv_sec = ival;
    109 		ntime.tv_nsec = fval;
    110 	}
    111 	else {
    112 		ntime.tv_sec = atol(arg);
    113 		if (ntime.tv_sec <= 0)
    114 			return EXIT_SUCCESS;
    115 		ntime.tv_nsec = 0;
    116 	}
    117 
    118 	if (nanosleep(&ntime, NULL) == -1)
    119 		err(EXIT_FAILURE, "nanosleep failed");
    120 
    121 	return EXIT_SUCCESS;
    122 	/* NOTREACHED */
    123 }
    124 
    125 void
    126 usage(void)
    127 {
    128 	(void)fprintf(stderr, "usage: %s seconds\n", getprogname());
    129 	exit(EXIT_FAILURE);
    130 	/* NOTREACHED */
    131 }
    132 
    133 /* ARGSUSED */
    134 void
    135 alarmhandle(int i)
    136 {
    137 	_exit(EXIT_SUCCESS);
    138 	/* NOTREACHED */
    139 }
    140