Starting

There is a wrapper function for creating each port type, start_port(). It accepts a mode argument and calls 4 lower-level wrapper functions.

Types of MIDI ports

There are virtual and non-virtual MIDI ports.

Think about virtual MIDI input and ouptut in terms of endpoints you connect to. “Normal” or “non-virtual” MIDI ports connect to those.

Client—server model, where a client 1 connects to a server is a nice analogy, as well. In this analogy, a server is a “virtual port” and a client is “just a port”.

Calling a wrapper

There is a single wrapper that is made of two parts: a port configurator (setup_port_config()) and a port starter (start_port()).

The table below shows some init examples and there’s more info in the examples section.

MIDI port type	Use	Init function
Input	Connect to	setup_port_config(&port_config, MP_IN); start_port(&amidi, port_config);
Output	Connect to	setup_port_config(&port_config, MP_OUT); start_port(&amidi, port_config);
Virtual input	Create an endpoint	setup_port_config(&port_config, MP_VIRTUAL_IN); start_port(&amidi, port_config);
Virtual output	Create an endpoint	setup_port_config(&port_config, MP_VIRTUAL_OUT); start_port(&amidi, port_config);

Installation

Just clone the repo and include the library as the examples show.

Requirements

• Alsa — should be already installed in your Linux distro

• GNU Make — generally available in your Linux distro

• glib-2.0 — libglib2.0-dev in Ubuntu

Footnotes

1

Alsa has its own client term , that has a different meaning: an Alsa seq client that has one or more ports as endpoints to communicate. Each port can be in a mode to read or write data and have other options.