Subject Database Errors: "Too many files open"
Author Eugene Lidede
I keep getting this error:

I/O error for file "<DB_FILENAME>" Error while trying to open file
Too many open files

I run Apache 1.3.39; Linux 2.6.9; with PHP 5.2.4 and firebird 1.5.4

The error started appearing a week ago out of the blues

What causes this error and how do i fix this

Regards