special characters in "file_exists" problem (php)

I use special characters (swedish letters åäö).

Now, I have some folders, which contains images for classifieds. The folders are named by category.

for ($i=1; $i<=5; $i++){
    if (file_exists($big_images.$i.'.jpg')){ echo "Inne";
        unlink($big_images.$i.'.jpg');
    }
    if (file_exists($thumb_images.$i.'.jpg')){
        unlink($thumb_images.$i.'.jpg');
        }
    }

I allow up to 5 images on my site, each ending with a nr 1-5. However, my problem is this, whenever the folder-name has a special character, the file_exists returns false, ie it doesn't find the file. Even though it is there.

All documents are in utf-8 format.

This works when there is no special characters in the folder names.

If you need more input let me know

What's the server OS?

If it's Windows, you'll not be able to access files under a UTF-8-encoded filename, because the Windows implementation of the C IO libraries used by PHP will only talk in the system default code page. For Western European installs, that's code page 1252. You can convert a UTF-8 string to cp1252 using iconv:

$winfilename= iconv('utf-8', 'cp1252', $utffilename);

(utf8_decode could also be used, but it would give the wrong results for Windows's extension characters that map to the range 0x80-0x9F in cp1252.)

Files whose names include characters outside the repertoire of the system codepage (eg. Greek on a Western box) cannot be accessed at all by PHP and other programs using the stdio. There are scripting languages that can use native-Unicode filenames through Win32 APIs, but PHP5 isn't one of them.

And of course the step above shouldn't be used when deployed on a different OS where the filesystem is UTF-8-encoded. (ie. modern Linux.)

If you need to seamlessly cross-server-compatible with PHP, you'll have to refrain from using non-ASCII characters in filenames. Sorry.