On all systems, dL4 files can be as large as 2 GB, which is the maximum file size supported by most Unix operating systems. On Linux, AIX, UnixWare, OpenUnix, or Windows NT/2000/XP systems, a new form of Portable file, called a "huge" file can be larger than 2 GB. A huge file is created with the "H" attribute or by using the dL4 makehuge utility to convert an existing file into a huge file. It may be necessary to configure special operating system or file system options in order to use huge files.