The same bug is in PHP 5.2.11 and Mac OS X 10.5

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

rename() can only work "normally" when operating on the same volume. 

In your case it emulates rename via copy & delete. I would guess since 
it cannot delete file from the original volume, it gives you an error 
message.

I understand, that rename can only operate on the same volume (like the move-command). But unlike in windows on a Mac (as on any other UNIX-like environment) volumes can be mount anywhere in the folder-hirachy, so that it is rather difficult to check whether source and target of the rename are on the same volume or not.

And as I pointed out in the original bug-report, the source-file actually is deleted, so there is no need for the error message.

Volumes can be mounted everywhere on windows as well. That does not change the fact that they are a different volume. Please read the underlying documentations for rename and how it works, that may help to understand the limitation.

The warnings may also be coming from the chown() and chmod() calls that occur between the copy and unlink when the rename call has to be faked across partitions -- there's no way of distinguishing them, since the warnings in php_plain_files_rename() just wrap strerror().

I wonder if this might be worth morphing into a doc bug: the rename manual page currently says that, as of 4.3.3, "rename() is now able to rename files across partitions on *nix based systems", which does seem to be overstating things a little. Something along the lines of "rename() may be able to rename files across partitions on *nix based systems, provided the appropriate permissions are held. Warnings may be thrown if the destination filesystem doesn't permit chown() or chmod() calls to be made on files." might be better.

I would like to second the suggestion of aharvey@php.net about making this a Documentation issue. I just spend 2 ours trying to figure out why rename() started spitting out warnings and still returned true.

It could be something like
<blockquote>
	<p>
		<b class="note">Note</b>:
		<span class="simpara">
If $oldname and $newname are on different partitions (on *nix based systems) the function might emit a warning "Warning: rename(oldfil,newfile): Operation not permitted" and still succeed. The reason is that internally the rename is done by copying the file, and attempting chown() and chmod() on the new file - and these operations can fail.
		</span>
	</p>
</blockquote>

FreeBSD, Apache 2.2, PHP 5.3.3.

Thanks for all the good work.

/Søren Thing

See your own comment :-)

This bug has been fixed in the documentation's XML sources. Since the
online and downloadable versions of the documentation need some time
to get updated, we would like to ask you to be a bit patient.

Thank you for the report, and for helping us make our documentation better.

Committed a slight variation on what I originally proposed, mostly to note that FAT filesystems are the most likely culprits here.

This isn't documented, for what I see. Am I right?

@jorgex0

No, you are not correct. The documentation has indeed been updated. From the Changelog section at http://php.net/rename :

4.3.3	rename() may now be able to rename files across partitions on *nix based systems, provided the appropriate permissions are held. Warnings may be generated if the destination filesystem doesn't permit chown() or chmod() system calls to be made on files — for example, if the destination filesystem is a FAT filesystem.

4.3.3	rename() may now be able to rename files across partitions on *nix based systems, provided the appropriate permissions are held. Warnings may be generated if the destination filesystem doesn't permit chown() or chmod() system calls to be made on files — for example, if the destination filesystem is a FAT filesystem.

Is no longer visible at: http://php.net/rename. Could you consider to add (or show) it again? I guess you don't show changelog entries for < PHP5 anymore.

Thanks!