Function for deleting old files throws "stat failed" error - php

Question

I am trying to use this simple bit of code to iterate through the "export" folder and delete files older than 24 hours:
if ($handle = opendir("/home/username/public_html/en/graphs/export")) {
while (false !== ($file = readdir($handle))) {
$filelastmodified = filemtime($file);
if((time() - $filelastmodified) > 24*3600)
{
unlink($file);
}
}
closedir($handle);
}
Some notes:
1) I do realize there are similar questions, but the solutions suggested there don't seem to work for me.
2) The absolute path to the directory is correct (tested)
3) The directory has 777 permissions. The files in it don't, but I tested with some files with 777 permissions and the same errors happened. So it doesn't seem to be a permission issue.
4) The file that contains this code is in a different directory (it's a cron job, I like to keep them together in a separate directory)
This is the error that appears (for each file in the directory):
Warning: filemtime() [function.filemtime]: stat failed for countries_rjRp9.png in /home/username/public_html/path-to-crons/crons/exports.php on line 12
Warning: unlink(countries_rjRp9.png) [function.unlink]: No such file or directory in /home/username/public_html/path-to-crons/crons/exports.php on line 16
In this example, countries_rjRp9.png is one of the files that should be unlinked from the export directory.
What's going on here?

Answer 1

You should specify the full path to unlink the file. In your loop, $file will be countries_rjRp9.png and you're trying to unlink it from the working directory, which is, the directory in which all of your cronjobs reside.
You state that the absolute path to your files is correct, but you forgot to use the absolute path once you're in your loop. You're only using an absolute path in your opendir() call, nowhere else.
Try doing something like this:
if ($handle = opendir("/home/username/public_html/en/graphs/export")) {
while (false !== ($file = readdir($handle))) {
// Take the filename and add its full path
$file = "/home/username/public_html/en/graphs/export/" . $file;
$filelastmodified = filemtime($file);
if((time() - $filelastmodified) > 24*3600)
{
unlink($file);
}
}
closedir($handle);
}