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<?php
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//$Header: /hl/cvsroots/gpl01/gpl01/webprojs/pamc/gen_a/sw/phplib/time/timeraw.inc,v 1.2 2007/06/24 03:38:09 dashley Exp $
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//--------------------------------------------------------------------------------
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//timeraw.inc -- PAMC functions for accessing low-level system time.
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//Copyright (C) 2007 David T. Ashley
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//--------------------------------------------------------------------------------
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//This program is free software; you can redistribute it and/or
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//modify it under the terms of the GNU General Public License
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//as published by the Free Software Foundation; either version 2
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//of the License, or (at your option) any later version.
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//
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//This program is distributed in the hope that it will be useful,
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//but WITHOUT ANY WARRANTY; without even the implied warranty of
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//MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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//GNU General Public License for more details.
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//
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//You should have received a copy of the GNU General Public License
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//along with this program; if not, write to the Free Software
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//Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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//--------------------------------------------------------------------------------
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//Author contact information:
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// David T. Ashley
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// P.O. Box 918
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// Marshall, Michigan, 49068
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// dta@e3ft.com
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//--------------------------------------------------------------------------------
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//This source file provides raw time related code. This file is a wrapper
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//around the built-in PHP functions to provide more flexibility as we get
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//near the Unix epoch. All functions that obtain from the machine time must
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//go through this module.
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//--------------------------------------------------------------------------------
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//Returns the current Unix time as an array of:
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// a)A decimal string representing the seconds since the Unix epoch. A string
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// representation is used because then this function can be modified as the
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// Unix epoch grows closer (but, we'll probably all be using 64-bit machines
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// by then). The string representation must not exceed 11 characters (but
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// this should not be a problem until after 5,000 A.D.).
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//
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// b)An integer representing the nanoseconds of the fractional part of the
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// Unix time. An integer is used because the fractional part of the time
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// is not affected by the Unix epoch issue.
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//
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//
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function TIMERAW_time_precision_mixed_array_2()
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{
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//Get the high-precision time microseconds and seconds.
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list($usec, $sec) = explode(" ", microtime());
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//Convert the integer seconds time to a string.
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$string_sec = sprintf("%d", $sec);
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//Convert the microseconds to an integer giving the
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//integer number of microseconds. The original value is in fractional
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//seconds (a float).
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$usec = $usec * 1000000.0;
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$usec = (int) $usec;
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//Convert microseconds to nanoseconds.
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$nsec = $usec * 1000;
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//Stuff the return array and return.
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$rv[0] = (string) $string_sec;
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$rv[1] = (int) $nsec;
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return($rv);
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}
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//--------------------------------------------------------------------------------
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//Returns the raw time, except that whole integer time values too near midnight
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//UTC won't be allowed. The reason for this behavior is to prevent a leap second
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//from allowing us to dwell in the same integer second twice, which would create
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//the possibility of sequential events having reversed timestamps or generating a
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//non-unique SGUID. The mechanism for failing to return these values potentially
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//corrupted by a leap second is that if one is the present time, sleep() will be
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//done to get out of the window. This will potentially delay a web page load or
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//maintenance script by up to approximately 4 seconds.
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//
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//Leap seconds, if they are injected or removed, will occur at midnight UTC.
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//
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function TIMERAW_time_precision_mixed_array_2_noleap()
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{
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$rv = TIMERAW_time_precision_mixed_array_2();
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$seconds_modulus = bcmod($rv[0], "86400");
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while (
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(bccomp($seconds_modulus, "2") == -1)
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||
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(bccomp($seconds_modulus, "86397") == 1)
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)
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{
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sleep(1);
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$rv = TIMERAW_time_precision_mixed_array_2();
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$seconds_modulus = bcmod($rv[0], "86400");
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}
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return($rv);
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}
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//--------------------------------------------------------------------------------
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//End of $RCSfile: timeraw.inc,v $.
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//--------------------------------------------------------------------------------
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?>
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