#42626 [NEW]: file operations in destructor cause weird results

From: admin at ifyouwantblood dot de Operating system: Windows XP SP2 PHP version: 5.2.4 PHP Bug Type: Class/Object related Bug description: file operations in destructor cause weird results Description: ------------ Calling clearstatcache() in destructor causes some very weird stuff. In the code below a file is created / truncated in the constructor. If you want to read the same file with fread in the destructor while it's still empty i'm expecting fread to print an error which it does. However if you write something to the file AFTER reading it and run the script twice fread returns what's written before. This should not happen, because before reading the file, we truncate it. Moreover if you continue calling the script, the string that fread returns contains all the writing operations done before. The strangest thing is, that it looks like that this behavior got something to do with the filename "datei.txt" (is German, means file.txt). If you change the filename, the fopen($this->filename,'r+') after clearstatcache() fails with the error "file does not exists". If you explicite truncate the file before reading it with ftruncate() no error is printed. If you remove clearstatcache() in the destructor it works as expected. This also appears on PHP 5.2.3 Reproduce code: --------------- <pre> <?php #call this script more than once! error_reporting(E_ALL|E_NOTICE); $test=new test; class test { private $filename='datei.txt'; public function __construct() { # open and truncate $file=fopen($this->filename,'w'); fclose($file); echo 'filesize after truncate: '.filesize($this->filename)."\n"; } public function __destruct() { echo 'Destructing test'."\n"; echo 'filesize before clearstatcache: '.filesize($this->filename)."\n"; clearstatcache(); echo 'filesize after clearstatcache: '.filesize($this->filename)."\n"; $file=fopen($this->filename,'r+'); if($file) { echo 'Reading file: '.fread($file,filesize($this->filename)); fputs($file,'aasadf'); } } } ?> Expected result: ---------------- filesize after truncate: 0 Destructing test filesize before clearstatcache: 0 filesize after clearstatcache: 0 Warning: fread() [function.fread]: Length parameter must be greater than 0 in G:\php\htdocs\cms\1jailbreak\admin\constructor.php on line 34 Reading file: Actual result: -------------- filesize after truncate: 0 Destructing test filesize before clearstatcache: 0 filesize after clearstatcache: 6 Reading file: aasadf ----- on repeated calling: filesize after truncate: 0 Destructing test filesize before clearstatcache: 0 filesize after clearstatcache: 12 Reading file: aasadfaasadf ----- filesize after truncate: 0 Destructing test filesize before clearstatcache: 0 filesize after clearstatcache: 18 Reading file: aasadfaasadfaasadf and so on... -- Edit bug report at http://bugs.php.net/?id=42626&edit=1 -- Try a CVS snapshot (PHP 4.4): http://bugs.php.net/fix.php?id=42626&r=trysnapshot44 Try a CVS snapshot (PHP 5.2): http://bugs.php.net/fix.php?id=42626&r=trysnapshot52 Try a CVS snapshot (PHP 6.0): http://bugs.php.net/fix.php?id=42626&r=trysnapshot60 Fixed in CVS: http://bugs.php.net/fix.php?id=42626&r=fixedcvs Fixed in release: http://bugs.php.net/fix.php?id=42626&r=alreadyfixed Need backtrace: http://bugs.php.net/fix.php?id=42626&r=needtrace Need Reproduce Script: http://bugs.php.net/fix.php?id=42626&r=needscript Try newer version: http://bugs.php.net/fix.php?id=42626&r=oldversion Not developer issue: http://bugs.php.net/fix.php?id=42626&r=support Expected behavior: http://bugs.php.net/fix.php?id=42626&r=notwrong Not enough info: http://bugs.php.net/fix.php?id=42626&r=notenoughinfo Submitted twice: http://bugs.php.net/fix.php?id=42626&r=submittedtwice register_globals: http://bugs.php.net/fix.php?id=42626&r=globals PHP 3 support discontinued: http://bugs.php.net/fix.php?id=42626&r=php3 Daylight Savings: http://bugs.php.net/fix.php?id=42626&r=dst IIS Stability: http://bugs.php.net/fix.php?id=42626&r=isapi Install GNU Sed: http://bugs.php.net/fix.php?id=42626&r=gnused Floating point limitations: http://bugs.php.net/fix.php?id=42626&r=float No Zend Extensions: http://bugs.php.net/fix.php?id=42626&r=nozend MySQL Configuration Error: http://bugs.php.net/fix.php?id=42626&r=mysqlcfg