IO::AIO implements fully asynchronous I/O (not
non-blocking I/O) that lets your program stay in
control and interactive even when doing heavy disk
(or other) I/O. It provides asynchronous versions
of read(), write(), open(), stat(), unlink(),
rename(), utime(), readlink(), and most other
standard syscalls as well as interfaces to
sendfile(), readahead(), and other esoteric
syscalls, complete with emulation on systems that
don't support them. It also offers convenience
functions to load whole files and more. It fits
naturally into any event loop model, supports 9
priorities and request grouping.