note 52738 deleted from function.strtotime by derick

From: Date: Sun, 15 Jul 2007 12:48:26 +0000
Subject: note 52738 deleted from function.strtotime by derick
References: 1  Groups: php.notes 
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Note Submitter: not provided ---- A shorter function for recognising dates before 1970 and returning a negative number is below. All it does is replaces years before 1970 with ones 68 years later (1904 becomes 1972), and then offsets the return value by a couple billion seconds. It works back to 1/1/1902, but only on dates that have a century. function safestrtotime ($s) { $basetime = 0; if (preg_match ("/19(\d\d)/", $s, $m) && ($m[1] < 70)) { $s = preg_replace ("/19\d\d/", 1900 + $m[1]+68, $s); $basetime = 0x80000000 + 1570448; } return $basetime + strtotime ($s); } Note that a negative number is stored the same as a really big positive number. 0x80000000 is the number of seconds between 13/12/1901 20:45:54 and 1/1/1970 00:00:00. And 1570448 is the seconds between this date and 1/1/1902 00:00:00, which is 68 years before 1/1/1970.

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