[PHP] Automated Numerical Filenames for Directory

[Smittie]

Hi everybody

Have this headache and hope there is someone that can help:

I need to generate numerical filenames in a directory, first filename being
20001.php

The next filename should be 20002.php etc.- no problem and easy enough

BUT, if you have files in the directory ;

20001.php
20002.php
20003.php
20004.php
20005.php

and you delete 20002.php, then the nexttime a new file is generated it
should be 20002.php and not 20006.php

Any ideas?

Thanks

Smittie