cacheout - keep more files open than the system permits
FileHandle
methods:
The cacheout() function will make sure that there's a filehandle open for writing available as the pathname you give it. It automatically closes and re-opens files if you exceed your system file descriptor maximum.
NOFILE
define on some systems,
so you may have to set $cacheout::maxopen yourself.
Due to backwards compatibility, all filehandles resemble objects
of class FileHandle
, or actually classes derived from that class.
They actually aren't. Which means you can't derive your own
class from FileHandle
and inherit those methods.