[LAU] command line midi processing

[Francesco Ariis]

Hello LAU,
    lately I have been playing with ABC notation [1].
ABC outputs to postscript/PDF and MIDI (a good output), but there
some things I would like to change in automatic fashion. Example:
anticipate the attack on some channels (string).
Is there a command line Linux utility to mess with midi files,
similar to what ImageMagick is for images?
I know plenty of libraries in many programming languages, but before
diving into those I would like not to reinvent the wheel.

[1] http://trillian.mit.edu/~jc/music/abc/doc/ABCtut_Intro.html