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      1 /*	$NetBSD: doze.c,v 1.1.1.1 2009/06/23 10:08:59 tron Exp $	*/
      2 
      3 /*++
      4 /* NAME
      5 /*	doze 3
      6 /* SUMMARY
      7 /*	take a nap
      8 /* SYNOPSIS
      9 /*	#include <iostuff.h>
     10 /*
     11 /*	void	doze(microseconds)
     12 /*	unsigned microseconds;
     13 /* DESCRIPTION
     14 /*	doze() sleeps for the specified number of microseconds. It is
     15 /*	a simple alternative for systems that lack usleep().
     16 /* DIAGNOSTICS
     17 /*	All errors are fatal.
     18 /* LICENSE
     19 /* .ad
     20 /* .fi
     21 /*	The Secure Mailer license must be distributed with this software.
     22 /* AUTHOR(S)
     23 /*	Wietse Venema
     24 /*	IBM T.J. Watson Research
     25 /*	P.O. Box 704
     26 /*	Yorktown Heights, NY 10598, USA
     27 /*--*/
     28 
     29 /* System library. */
     30 
     31 #include "sys_defs.h"
     32 #include <sys/time.h>
     33 #include <unistd.h>
     34 #include <errno.h>
     35 #ifdef USE_SYS_SELECT_H
     36 #include <sys/select.h>
     37 #endif
     38 
     39 /* Utility library. */
     40 
     41 #include <msg.h>
     42 #include <iostuff.h>
     43 
     44 /* doze - sleep a while */
     45 
     46 void    doze(unsigned delay)
     47 {
     48     struct timeval tv;
     49 
     50 #define MILLION	1000000
     51 
     52     tv.tv_sec = delay / MILLION;
     53     tv.tv_usec = delay % MILLION;
     54     while (select(0, (fd_set *) 0, (fd_set *) 0, (fd_set *) 0, &tv) < 0)
     55 	if (errno != EINTR)
     56 	    msg_fatal("doze: select: %m");
     57 }
     58 
     59 #ifdef TEST
     60 
     61 #include <stdlib.h>
     62 
     63 int     main(int argc, char **argv)
     64 {
     65     unsigned delay;
     66 
     67     if (argc != 2 || (delay = atol(argv[1])) == 0)
     68 	msg_fatal("usage: %s microseconds", argv[0]);
     69     doze(delay);
     70     exit(0);
     71 }
     72 
     73 #endif
     74