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How to use h2cli

5 replies [Last post]
Joined: 01/24/2013



Like in subject - how to use it ? I'm not sure it is actually healty (doesn't display any prompt)

Hydrogen 0.9.6-beta3 [Feb 25 2013]  []
Copyright 2002-2008 Alessandro Cominu

Hydrogen comes with ABSOLUTELY NO WARRANTY
This is free software, and you are welcome to redistribute it
under certain conditions. See the file COPYING for details

Cannot lock down 107335194 byte memory area (Cannot allocate memory)
Cannot use real-time scheduling (RR/5)(1: Operation not permitted)
JackClient::AcquireSelfRealTime error

thijs's picture
Joined: 04/20/2010


i have never used the h2cli

however, the error you get (the last 3 lines) sound like jack messages and not H2 messages

my guess is that h2cli starts H2 using the Jack driver, but there seems to be some misconfig of the jack parameters (looks like a permission issue)

can you try this :

- start Jack the normal way (via qjackctl for example)

- make sure jack is running and working ok 

- then start h2 via the h2cli command

and see what happens

(also make sure that you are starting jack and h2cli as the same user)

Joined: 01/24/2013

I thought this is obvious question, but seems wasn't, so I look into the code and now I know that this app almost do nothing ;-) It load song,drumkit and initialize audio driver (in my setup connect to jack) - then it hang in endless loop.

First hint what it is , is in first code line "A headless attempt for hydrogen" ;-)

In line 269 there is:

while (true) {


You can probably control it via midi - but I wasn't dig that deep. Maybe this will be usefull for other users.

Joined: 03/30/2010


I wrote h2cli to support people who are visually impaired and cannot use the regular user interface of hydrogen. As you already found out, the command line version has no big feature set. It is mostly thought as a sampler which gets its input via midi. Besides the support for folks who can't use a gui, it was an experiment to see how easy it is to seperate the gui from the core of hydrogen.

Joined: 01/24/2013

For me this app is one of the greatest thing in hydrogen. I plan someday help with improve this - but currently I have lot of tasks in opensource area.

How do you thing - it will be hard to implement export to file function ? Let me explain my goals. I use hydrogen in my band as drum machine, we still building song - lot of changes on each attempt. Then I use svn for this. Later when I back to home I need to create ogg versions. I want to automize this processs by script. h2cli seems to be pretty close to achieve this.