The "file" and "files" variants fetch the specified files and attempt to import the tiddlers within them (the same processing as if the files were dragged into the browser window). The "raw-file" and "raw-files" variants fetch the specified files and then store the raw file data in tiddlers, without applying the import logic.
With the "files" and "raw-files" variants, multiple files are fetched and the first parameter is a filter yielding a list of URLs of the files to read. For example, given a set of tiddlers tagged "remote-server" that have a field "url" the filter `[tag[remote-server]get[url]]` will retrieve all the available URLs.
For the "file" and "files" variants, the `<import-filter>` parameter specifies a filter determining which tiddlers are imported. It defaults to `[all[tiddlers]]` if not provided.
For all variants, the `<transform-filter>` parameter specifies an optional filter that transforms the titles of the imported tiddlers. For example, `[addprefix[$:/myimports/]]` would add the prefix `$:/myimports/` to each title.
The following example retrieves the "favicon" file from tiddlywiki.com and saves it in a file called "output.ico". Note that the intermediate tiddler "Icon Tiddler" is quoted in the "--fetch" command because it is being used as a transformation filter to replace the default title, while there are no quotes for the "--savetiddler" command because it is being used directly as a title.
