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<?php
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if (!isset($PAMC_A_TIME_TIMERAW_INCLUDED))
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{
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include("pamc_a/time/timeraw.inc");
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$PAMC_A_TIME_TIMERAW_INCLUDED=1;
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}
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?>
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<?php
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//********************************************************************************
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//Copyright (C) 2006 David T. Ashley
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//********************************************************************************
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//This program or source file is free software; you can redistribute it and/or
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//modify it under the terms of the GNU General Public License as published by
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//the Free Software Foundation; either version 2 of the License, or (at your
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//option) any later version.
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//
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//This program or source file is distributed in the hope that it will
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//be useful, 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 may 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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//********************************************************************************
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//Dave Ashley, 01/06
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//
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//This source file provides the code to create process-unique
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//timestamps. A process-unique timestamp is guaranteed to be unique
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//because this code will spin-lock until the time changes.
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//
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//A process-unique timestamp is 72 bits of information (18 hexadecimal
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//digits). The breakdown is:
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//
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// a)First 40 bits (10 hexadecimal digits). The integer time, in seconds
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// since the Unix epoch. The extra 8 bits are reserved due to the impending
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// Unix 2037 AD issue.
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//
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// b)Second 32 bits (8 hexadecimal digits). The nanoseconds representing the
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// fractional part of the integer seconds.
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//
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//Note that both of the data sizes above are designed to allow future
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//expansion. The integer part is designed for the Unix 2037 issue. The
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//fractional part is designed for faster hardware in the future.
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//
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//
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function PUTS_timestamp()
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{
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//Obtain the initial value.
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$rv = TIMERAW_time_precision_hex();
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//Wait for the time to change. Although I don't think it would make a difference
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//in practice, there is sleep to be more efficient.
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$new_time = TIMERAW_time_precision_hex();
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if ($rv == $new_time)
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{
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do
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{
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usleep(100);
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$new_time = TIMERAW_time_precision_hex();
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}
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while ($rv == $new_time);
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}
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//The time has changed. We are clear to return.
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return($rv);
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}
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//
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//
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//Returns the size (in chars) of a process-unique timestamp.
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//
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function PUTS_timestamp_size()
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{
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return(TIMERAW_time_precision_hex_size());
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}
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?>
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