#46197 [Opn->Fbk]: Problems with file_exists() and multiple instances
ID: 46197
Updated by: jani@php.net
-Summary: Problems with file_exists and multiple instances
Reported By: henrique dot grolli at gmail dot com
-Status: Open
+Status: Feedback
Bug Type: Filesystem function related
Operating System: *
PHP Version: 5.2.6
New Comment:
Is the webserver by any chance threaded?
See also http://php.net/flock for proper locking method.
Previous Comments:
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[2008-10-05 04:17:06] kalle@php.net
I can reproduce this under Windows Vista with Apache 2
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[2008-09-29 15:12:10] henrique dot grolli at gmail dot com
Description:
------------
Well, better explained when seeing the code.
Not acting as expected via web browser as the both instances execute as
the lock file was not created by another instance but doing it well via
shell console.
Same problem using clearstatcache() function.
Reproduce code:
---------------
// LOCK_FILE was defined to /tmp/test.lock
// creating the lock file
if(file_exists(LOCK_FILE)) {
echo "ANOTHER INSTANCE RUNNING\n";
exit(1);
}
else {
touch(LOCK_FILE);
}
/* any action that takes time*/
echo "running\n";
sleep(5); // simulating slow scripts
echo "done\n";
if(file_exists(LOCK_FILE)) {
unlink(LOCK_FILE);
}
else {
echo "I think someone deleted the lock file\n";
}
Expected result:
----------------
To see "running\ndone\n" in one instance, and "ANOTHER INSTANCE
RUNNING\n" if another instance try to execute at the same time.
Actual result:
--------------
Via shell everything works as well but via web browser both instances
run as the lock file doesnt exist.
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Edit this bug report at http://bugs.php.net/?id=46197&edit=1
Thread (3 messages)