# PerlIO::mmap - phpMan

## NAME
    [PerlIO::mmap] - Memory mapped IO

## SYNOPSIS
     open my $fh, '<:mmap', $filename;

## DESCRIPTION
    This layer does "read" and "write" operations by mmap()ing the file if
    possible, but falls back to the default behavior if not.

## IMPLEMENTATION NOTE
    "[PerlIO::mmap]" only exists to use XSLoader to load C code that provides
    support for using memory mapped IO. One does not need to explicitly "use
    [PerlIO::mmap];".