There may be two ways how you can link AgsChannel objects.
Example 6.2. Prerequisites
#include <glib.h>
#include <glib-object.h>
#include <ags/libags.h>
#include <ags/libags-audio.h>
AgsAudio *master_audio, *slave_audio;
AgsLinkChannel *linkChannel;
AgsApplicationContext *application_context;
AgsTaskLauncher *task_launcher;
GObject *soundcard;
GError *error;
application_context = ags_application_context_get_instance();
task_launcher = ags_concurrency_provider_get_task_launcher(AGS_CONCURRENCY_PROVIDER(application_context));
/* create AgsAudio objects */
master_audio = (AgsAudio *) g_object_new(AGS_TYPE_AUDIO,
"soundcard", soundcard,
NULL);
slave_audio = (AgsAudio *) g_object_new(AGS_TYPE_AUDIO,
"soundcard", soundcard,
NULL);
/* assign AgsAudioSignal objects to master_audio and slave_audio */
ags_audio_set_flags(master_audio,
AGS_AUDIO_OUTPUT_HAS_RECYCLING);
ags_audio_set_flags(slave_audio,
(AGS_AUDIO_ASYNC | AGS_AUDIO_OUTPUT_HAS_RECYCLING | AGS_AUDIO_INPUT_HAS_RECYCLING));
/* create AgsChannel objects within master_audio and slave_audio */
ags_audio_set_audio_channels(master_audio, 2);
ags_audio_set_pads(master_audio, AGS_TYPE_OUTPUT, 1);
ags_audio_set_pads(master_audio, AGS_TYPE_INPUT, 1);
ags_audio_set_audio_channels(slave_audio, 2);
ags_audio_set_pads(slave_audio, AGS_TYPE_OUTPUT, 1);
ags_audio_set_pads(slave_audio, AGS_TYPE_INPUT, 8);
Assumed you know really what you do, you may be interested in following code.
Example 6.3. Thread-Unsafe way
/* link master_audio's input with slave_audio's output */
ags_channel_set_link(ags_channel_nth(master_audio->input, 0),
ags_channel_nth(slave_audio->output, 0),
&error);
ags_channel_set_link(ags_channel_nth(master_audio->input, 1),
ags_channel_nth(slave_audio->output, 1),
&error);
But generally you wish to create an AgsTask object and let it to link the AgsChannel for you.
Example 6.4. Multithread-Safe way
/* creating AgsLink task and add it to AgsDevout */
link_channel = ags_link_channel_new(ags_channel_nth(master_audio->input, 0),
ags_channel_nth(slave_audio->output, 0));
ags_task_launcher_add_task(task_launcher,
link_channel);
link_channel = ags_link_channel_new(ags_channel_nth(master_audio->input, 1),
ags_channel_nth(slave_audio->output, 1));
ags_task_launcher_add_task(task_launcher,
link_channel);