The FileIO Xtra is used to read and write text files, but it can not access remote URLs (use NetLingo commands such as getNetText), nor is it designed for binary files (see the BinaryIO Xtra at http://www.updatestage.com/xtras/).
Director 4 used the older FileIO XObject. Director 5 included both the XObject and the Xtra versions, which conflicted if they were both used.
The older Macintosh FileIO XObject was embedded in the resource fork of the Director 4 and 5 authoring package and D4 Projectors (but not D5 Projectors). The XObject is discontinued in D6, but it is included in a separate resource file under Director 6 CD:Macromedia:Discontinued:FileIO XObject:FileIO XObject.rsrc.
The older Windows FileIO XObject (that is, FILEIO.DLL) was opened automatically during authoring in D4 and D5 via an
openXlib command in the
on startUp handler in the default LINGO.INI file. To use it from a Windows Projector you had to include FILEIO.DLL with the Projector and either use
openXlib or the default LINGO.INI file to open it. (See Appendix D, for details on LINGO.INI.) Under Windows, FILEIO.DLL is no longer installed by default, but it can be found on the D6 for Windows CD under D:\Macromedia\Discontinued\FileIO XObject\Fileio.dll. It is not compatible with 32-bit Projectors and should not be used any more.
If using Director 5 or 6, you should use version 1.0.3 (or later) of the FileIO Xtra. The FileIO Xtra is installed by default in the
Xtras/Media Support folder one level down from Director. ...