func Glob(fs http.FileSystem, pattern string) (matches []string, err error)
Glob returns the names of all files matching pattern or nil if there is no matching file. The syntax of patterns is the same as in path.Match. The pattern may describe hierarchical names such as /usr/*/bin/ed.
Glob ignores file system errors such as I/O errors reading directories. The only possible returned error is ErrBadPattern, when pattern is malformed.