[ecasound] how to properly slave ecasound to jack transport?

From: Claude Heiland-Allen <claudiusmaximus@email-addr-hidden>
Date: Sat Sep 25 2010 - 19:34:29 EEST

Hi everyone,

I'm probably missing something really obvious, but I can't seem to
figure out the correct incantations to get ecasound to be a JACK
transport slave, starting in a paused state (possibly disconnected from
all other JACK audio ports) until some other application (one I wrote,
so it's probably buggy...) connects the ports and starts the transport,
at which point ecasound should record until the transport is stopped by
the other application.

Attached is a gzip'd log file from one failed attempt (also containing
output from the other components in the same script), the key parts seem
to be this section:

(eca-engine) Using realtime-scheduling (SCHED_FIFO:50).
(audioio_jack_manager) jack_activate()
(eca-engine) Request start
(audioio_jack_manager) driver start
(eca-engine) starting engine operation!
(audioio_jack) start / jack
(audioio-db-server) wait_for_client_activity failed
(eca-engine) Request stop
(audioio_jack_manager) driver stop
(eca-engine) stopping engine operation!
(audioio_jack) stop / jack
(audioio-db-server) stop
(audioio-db-server) wait_for_client_activity failed
(eca-engine) Changed back to non-realtime scheduling SCHED_OTHER.

which all happens in a blink of an eye - ecasound appears in qjackctl
connections pane and vanishes immediately.

Using ecasound as found in up-to-date Lucid i386 ( sorry, not booted
into that install right now, but I assume it'll be the same as Lucid
64bit: ecasound-2.7.0-1build1 )

Without ,recv in the jack options it "works" (ie, doesn't quit
immediately) but records from when it was launched, instead of from when
the transport is started (later on).

Also (possibly related?) I had to manually set the "TERM" environment
variable to "linux" to avoid ecasound aborting on launch from a bash
script started by a desktop icon.

Thanks for any insight,



Start uncovering the many advantages of virtual appliances
and start using them to simplify application deployment and
accelerate your shift to cloud computing.

Ecasound-list mailing list

Received on Sat Sep 25 20:15:03 2010

This archive was generated by hypermail 2.1.8 : Sat Sep 25 2010 - 20:15:04 EEST