Each "file" argument may be one of the following types:
A regular file name. If more than one file exists with that name, then a list will be shown and you will be able to pick the exact file.
A symbol name. Since Source Insight treats file names as symbols, each file argument can be more generally thought of as a symbol. Source Insight will open the file where the symbol lives and jump to its location. You may specify any number of symbols. If the symbol name conflicts with file names (without extensions), or with other symbols, then a list will be shown and you will be able to pick the exact symbol instance.
The name of a workspace file, including the .siwork extension. Source Insight will open all the files contained in the workspace.