ID: 28790
Comment by: phpbugs at spam dot raszi dot hu
Reported By: jnoll at prim dot hu
Status: Assigned
Bug Type: Feature/Change Request
Operating System: Debian GNU/Linux (unstable)
PHP Version: 4.3.6
Assigned To: pollita
New Comment:
It would be better if the file modification functions invalidate not
the whole statcache, only the entry of the modified file.
Previous Comments:
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[2004-06-16 16:29:51] pollita@php.net
Ilia was perhaps a bit short winded in his response...
This was actually discussed within the context of a feature change as
well and was turned down on the basis that it would create unnecessary
slowdowns without significant gain.
You should be aware when you're making multiple stat family calls to
the same file and call clearstatcache() accordingly. If you're
uncertain, then just call it anyway.
However, that said it may be prudent to introduce an .ini option to
disable the cache altogether now that stat calls work on arbitrary
wrappers. Let's leave this option open for PHP 5.1 for now.
------------------------------------------------------------------------
[2004-06-16 16:10:36] jnoll at prim dot hu
Okay, let me change this to a feature request!
After fclose(), the stat cache for that file should be cleared. Also,
unlink and maybe copy should do this.
If a function is KNOWN to change file stat data, it should clear the
cache.
The problem is that even a file_exists() call caches the data
(including the file size!), and this is easy to overlook, when you have
a bigger system.
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[2004-06-15 19:03:34] iliaa@php.net
Thank you for taking the time to write to us, but this is not
a bug. Please double-check the documentation available at
http://www.php.net/manual/ and the instructions on how to
report
a bug at http://bugs.php.net/how-to-report.php
This is to be expected.
------------------------------------------------------------------------
[2004-06-15 15:43:13] jnoll at prim dot hu
Description:
------------
The problem is the following:
1. open a file for writing or appending
2. append a character (or anything) to that file
3. close file
4. get the file size with stat or filesize
ERROR: this will return the OLD size, before writing
If you do a clearstatcache(), the filesize will be the NEW size (the
expected result)
Reproduce code:
---------------
<?
$filename = "/tmp/stattest";
// initialise
if (!file_exists($filename)) {
$f = fopen($filename,"w");
fclose($f);
echo "Reload, please.";
exit;
}
$fs = filesize($filename); $fstat = stat($filename);
echo "START: $fs, ".$fstat['size']."<BR>";
$f = fopen($filename,"a");
fputs($f,"x");
fclose($f);
/**
* bad result: this should be 1 byte more than the previous
* BUT IT IS THE SAME!!!
*/
$fs = filesize($filename); $fstat = stat($filename);
echo "AFTER(BAD): $fs, ".$fstat['size']."<BR>";
// force a clear
clearstatcache();
/**
* good result after clearstatcache (why???)
*/
$fs = filesize($filename); $fstat = stat($filename);
echo "AFTER(GOOD): $fs, ".$fstat['size']."<BR>";
?>
Expected result:
----------------
START: 145, 145
AFTER(BAD): 145, 145
AFTER(GOOD): 146, 146
If AFTER(BAD) is less than AFTER(GOOD) value, that means PHP is buggy.
------------------------------------------------------------------------
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Edit this bug report at http://bugs.php.net/?id=28790&edit=1