mod-host is an LV2 host for Jack, that can be controlled via a socket or shell.

Currently the host supports the following LV2 features:

• lv2core
• atom
• event
• buf-size
• midi
• options
• uri-map
• urid
• worker

mod-host is part of the MOD project.

mod-host uses a simple Makefile to build the source code. The steps to build and install are:

make
sudo make install

The default instalation path is /usr/local/bin, this can be modified passing the variable INSTALL_PATH to make install, e.g.:

sudo make install INSTALL_PATH=/usr/bin

Dependencies:

libjack-jackd2  >= 1.9.8
liblilv         >= 0.14.2
libargtable2    >= 2.13
libreadline     >= 6.2

mod-host does not startup JACK automatically, so you need to start it before run mod-host.

If you run mod-host without parameters the process will be forked and can only be controlled through the socket. The default socket port is 5555, this can be changed, passing the parameter -p (or --socket-port) to mod-host.

The other way to control mod-host is the interactive mode, in this case the commands must be provided on the shell prompt. When you are in the interactive mode, the socket communication does not work.

The commands supported by mod-host are:

add <lv2_uri> <instance_number>
    e.g.: add http://lv2plug.in/plugins/eg-amp 0
    instance_number must be any value between 0 ~ 9999, inclusively

remove <instance_number>
    e.g.: remove 0

connect <origin_port> <destination_port>
    e.g.: connect system:capture_1 effect_0:in

disconnect <origin_port> <destination_port>
    e.g.: disconnect system:capture_1 effect_0:in

param_set <instance_number> <param_symbol> <param_value>
    e.g.: param_set 0 gain 2.50

param_get <instance_number> <param_symbol>
    e.g.: param_get 0 gain

param_monitor <instance_number> <param_symbol> <cond_op> <value>
    e.g: param_monitor 0 gain > 2.50

monitor <addr> <port> <status>
    e.g: monitor localhost 12345 1

bypass <instance_number> <bypass_value>
    e.g.: bypass 0 1
    bypass_value = 1 bypass the effect and bypass_value = 0 process the effect

load <filename>
    e.g.: load my_preset

save <filename>
    e.g.: save my_preset
    this command saves the history of typed commands

help
    show a help message

quit
    bye!

For each effect added, one client on JACK will be created. The names of clients follow the standard: effect_<instance_number>

For each command sent, one response is given. If the command is valid, the response format will be:

resp <status> [value]

If status is a negative number, an error occurred. The error will be one of the following:

A status of zero or positive means, that the command was executed successfully. In case of the add command, the status returned is the instance number. The value field currently only exists for the param_get command.