mkdir() call in a theme?

[Ryan]

A friend of mine showed me a site of his which is spitting out the following message on updating options in the theme options page after upgrading his theme to the latest version:

Warning: mkdir() [function.mkdir]: Permission denied

He needed to upgrade the theme because the original was no longer working with the current version of WordPress. But why on earth would a theme need to use mkdir()? The error seems to be related to a line which is trying to create a directory with file permissions of 777. I can't see why a theme would need to create a directory let alone require it to have file permissions of 777.


The theme was OpenAir by Woo Themes.
Has anyone else had this problem with Woo Themes themes before? Any ideas on how to get around it?

[Len]

Is the theme using some sort of auto image resizer script that stores images in a cache folder it created? Cache folder having permissions of 777? Dunno, just a thought.

[Ryan]

Hmm, maybe it's a thumbnail'ing system perhaps. Although I'd have thought the regular uploads directory would be a much smarter place to store anything like that rather than the theme folder itself.

[ledfrog]

I'm not sure if you ever solved this or not, but in case you didn't or someone else needs the help, here's all you need to do.

The rest of that error should tell you what file and what line of code is giving you the problem. If you look in the file on that line, you'll find the code that says something about "mkdir" and they'll be a direction name that it's trying to make.

Just navigate to the location of that directory on your server and give write permissions to the folder. Problem solved.

[Ryan]

That may solve the problem, but it doesn't explain why it would need to write to the server.

[Otto]

Without actually seeing the code, it's difficult to say why it would be trying to do that.

As a matter of good WordPress coding practice, plugins and themes should never create any files/folders outside of the uploads folder. Nowhere else is guaranteed to have permissions set so that you can write there.

[Ryan]

As a matter of good WordPress coding practice, plugins and themes should never create any files/folders outside of the uploads folder.

Is there any procedure on how/where to do that?

It seems odd to just dump files randomly into the folder, but if that's the way to do it then that's what I'll do!

[Otto]

Is there any procedure on how/where to do that?

It seems odd to just dump files randomly into the folder, but if that's the way to do it then that's what I'll do!

First you call wp_upload_dir, to get the upload directory. This actually returns an array with several possible directories to choose from.

From here, you have several choices, depending on what you're doing. You pick one of the directories from the array, and you can even add yourself a subdirectory name onto it, if you like.

Next you would call wp_unique_filename($dir, $filename), in order to obtain a filename that doesn't conflict with any existing names there.

Once you have those, you just use normal PHP file functions to create and write whatever you like to the file.

If you want to use uploading from the browser, then there's a lot of functions to handle that in WordPress without doing the above. wp_handle_upload() is the big one that does all the work.

If you want to create a new file and don't really care where it goes, look at wp_upload_bits().

[Ryan]

Thanks Otto :)