tom | 20 Oct 05:08 2014

Fwd: Re: jack_connect with many channels

btw this is the backtrace of the client having that issue:
i've tried to strip it down so it does practically the same as the test 
program which hasn't the issue. also why 
the bogus client can work with jack2 is a riddle for me. I'll look 

-------- Original Message --------
Subject: Re: [Jack-Devel] jack_connect with many channels
Date: 2014-10-20 04:47
 From: tom <at>
To: jack-devel <at>

Hello Robin

a small test program one seems to work. Hm. I guess i have to look 
further why practically the same code doesn't work in another client. 


On 2014-10-20 01:20, Robin Gareus wrote:
>> On Oct 19, 2014, at 8:17 PM, tom <at> wrote:
>> Hi
(Continue reading)

tom | 19 Oct 20:17 2014

jack_connect with many channels


i use the following code snippet to connect all available hardware/system
capture ports to a client:


    int j=0;
    int i=0;
      if (ports[i]!=NULL)
        if(!jack_connect (client, ports[i],jack_port_name(ioPortArray[j])))
          fprintf (stderr, "autoconnect: %s -> %s\n",
          fprintf (stderr, "autoconnect: failed: %s -> %s\n",
(Continue reading)

Rui Nuno Capela | 19 Oct 22:48 2014

[ANN] QjackCtl 0.3.12 released, feat. JACK Pretty-names aliasing

Again, a classic needs no introduction...

   QjackCtl 0.3.12 is now released!

- JACK client/port pretty-name (metadata) support is being introduced 
and seamlessly integrated with old Connections client/port aliases 
editing (rename) (refactored from an original patch by Paul Davis, 
- Application close confirm warning is now raising the main window as 
visible and active for due top level display, especially applicable when 
minimized to the system tray.
- Messages standard output capture has been slightly improved as for 
non-blocking i/o, whenever available.
- Translations install directory change.
- Allow the build system to include an user specified LDFLAGS.
- Missing input/output-latency parameter settings now settled for the 
D-BUS controlled JACK server and firewire back-end driver.


Project page:

- source tarball:
- source package (openSUSE 13.1):

(Continue reading)

Daniel Hams | 16 Oct 22:28 2014

Jack1 Questions

Hi jack-devel,

I'm embarking on a journey to learn the jack server internals and how it works. As part of that I'm doing a
little C++'ifying of the jack1 source.

Why didn't I look at jack2 which is already C++? It’s easier for me to learn by doing some coding and jack1
seems to be less of a moving target for that.

As such, I have a couple of questions about the jack1 source that perhaps some of the esteemed people on this
list could help me with.

If this isn't the place for this and you'd rather not have it on the list, just let me know.

* jack_load_internal_clients (jackd.c:95)

I've tested the formats from the comments and see the following

client-name:client-type/args - parses as "(client-name)(client-type)(args)"
client-type/args             - fails due to client-name being NULL
client-name:client-type      - parses as "(client-name)(client-type)(NULL)"
client-type                  - parses as "(client-type)(client-type)(NULL)"

The second one seems to contradict the comments in the code (not outrageous, we've all done it).
I’ve copied the behaviour for now. Perhaps it should mirror the fourth one in copying the client-type
into the client-name?

* Unblocking of signals

controlapi.c:841 uses SIG_SETMASK to pthread_sigmask to unblock signals
jackd.c:382 uses SIG_UNBLOCK to sigprocmask to unblock signals
(Continue reading)

Matt Flax | 9 Oct 06:42 2014

netjack2 on cygwin

Hi there,

I am trying to compile jack2 netjack on cygwin.

After manually compileing celt and opus, I am now having troubles with 
standard compilation in the windows directory ... and other stuff.

For example the JackAtomic asm stuff is troublesome !

Has anyone managed to compile netjack for cygwin ?

Matt Flax | 9 Oct 02:53 2014

port disconnection callbacks (JackPortConnectCallback)

Hi there,

I have registered a callback for port (dis)connections.

When my client connects its ports, the JackPortConnectCallback indicates 
this occurance with the 'connect' variable = 1

When my client finishes playing, it stops by returning a non-zero number 
from the audio processing function. If I stop the client in this manner, 
then my JackPortConnectCallback doesn't get called.

I can see that the port has been disconnected from the client's inputs 
and outputs.

I would expect that when the system disconnects those ports it calls the 
JackPortConnectCallback with the 'connect' variable = 0

Is this the expected behaviour ?

Here is the version info :
jackdmp 1.9.10

Robin Gareus | 4 Oct 23:48 2014

jack2 ASIO & autostart

Hi Stephane. Hi jack2-devs.

In a recent foray into the windows-world, I noticed that that when
installing jack2, it registers JackRouter.dll ASIO dll. So far so good.

When starting some ASIO application that scans for available devices and
if jackd is not running, JackRouter.dll tries to launch jackd during
ASIO device scan. Not good.

jackd's auto-start timeout is about 1 min which makes this rather
unusable. See for a complete log.
It takes twice that time if ASIO4all is installed which probes
JackRouter again.

Here, jackd auto-start fails because jackd on win7 64bit installs itself
to C:\Program Files (x86)\Jack\jackd.exe (note the x86) -- but even if
jackd autostart is made to work, jackd blocks the device which one may
want to use directly with ASIO and causes further issues...

Current workaround: start jackd with the dummy backend before launching
an ASIO app, or uninstall jack.

Proposed solution: use JackNoStartServer in JackRouter (patch attached).

(Continue reading)

Tim E. Real | 4 Oct 08:54 2014

JackPortRenameCallback incompatible in Jack 1/2

In types.h :


typedef void (*JackPortRenameCallback)(jack_port_id_t port, const char* 
old_name, const char* new_name, void* arg);


typedef int (*JackPortRenameCallback)(jack_port_id_t port, const char* 
old_name, const char* new_name, void *arg);

./muse2: symbol lookup error: ....lib/muse-2.1/modules/ 
undefined symbol: jack_set_port_rename_callback

App was compiled with Jack2. 
Jack1 is installed.

Jörn Nettingsmeier | 29 Sep 21:08 2014

JACK1 git repo fails to build from source

Hi *,

there is a typo in the jack1 repo that prevents it from building:

--- libjack/intclient.c~	2014-09-29 21:06:09.000000000 +0200
+++ libjack/intclient.c	2014-09-29 21:06:50.032005928 +0200
 <at>  <at>  -119,7 +119,7  <at>  <at> 
  jack_internal_client_handle (jack_client_t *client,
  			     const char *client_name,
  			     jack_status_t *status,
-                             jack_intclient_t *handle)
+                             jack_intclient_t handle)
  	jack_request_t req;
  	jack_status_t my_status;

All best,



Jörn Nettingsmeier
Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487

Meister für Veranstaltungstechnik (Bühne/Studio)
Tonmeister VDT

(Continue reading)

Tim E. Real | 28 Sep 01:47 2014

Jack2 alsarawmidi slave: Pluggable device registration problem?


When I plug in my USB midi device after starting Jack2 with alsarawmidi,
 it does not register at all, as jack_lsp shows.

But if I instead start Jack2 after the device is plugged in, ports are there.

But then if I unplug the device, strangely the ports do not unregister and 
 I can even make connections to them in qjctl.

Having seen the second problem first, I thought it might be a new 'feature' - 
 Persistent Ports!

But now having seen the first problem I guess not...

What could be wrong?
Thanks. Tim.
Adrian Knoth | 18 Sep 18:34 2014

[jackaudio/jack1] 939286: Fix FTBFS with clang

  Branch: refs/heads/master
  Commit: 93928654345994ae4b6d6d8e83c946a1075d5db9
  Author: Adrian Knoth <adi <at>>
  Date:   2014-09-18 (Thu, 18 Sep 2014)

  Changed paths:
    M drivers/alsa/memops.c

  Log Message:
  Fix FTBFS with clang

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