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-defaultextension => *extension*
Specifies a string that will be appended to the filename if the user
enters a filename without an extension. The default value is the
empty string, which means no extension will be appended to the
filename in any case. This option is ignored on the Macintosh
platform, which does not require extensions to filenames.

-filetypes => [*filePattern* ?, ...?]
If a File types listbox exists in the file dialog on the particular
platform, this option gives the *filetype*s in this listbox. When
the user choose a filetype in the listbox, only the files of that
type are listed. If this option is unspecified, or if it is set to
the empty list, or if the File types listbox is not supported by the
particular platform then all files are listed regardless of their
types. See "SPECIFYING FILE PATTERNS" below for a discussion on the
contents of *filePattern*s.

-initialdir => *directory*
Specifies that the files in *directory* should be displayed when the
dialog pops up. If this parameter is not specified, then the files
in the current working directory are displayed. This option may not
always work on the Macintosh. This is not a bug. Rather, the
*General Controls* control panel on the Mac allows the end user to
override the application default directory.

-initialfile => *filename*
Specifies a filename to be displayed in the dialog when it pops up.
This option is ignored by the getOpenFile method.

-title => *titleString*
Specifies a string to display as the title of the dialog box. If
this option is not specified, then a default title is displayed.
This option is ignored on the Macintosh platform.