Format sets the SMF file format version.

New returns a Writer The writer just uses an io.Writer..It is the responsibility of the caller to open and close any file where appropriate.

NoRunningStatus forces the writer to always write the status byte.

NumTracks sets the number of tracks in the file.

TimeFormat sets the timeformat.

WriteFile creates file, calls callback with a writer and closes file WriteFile makes sure that the data of the last track is written by sending an meta.EndOfTrack message after callback has been run.