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#include <stdio.h>
#include <stdlib.h>
#include <alsa/asoundlib.h>
int main(int argc, char *argv[]) {
struct snd_mixer_selem_regopt smixer_options;
int err, ival;
char card[64] = "default";
long lval;
static snd_mixer_t *handle = NULL;
snd_mixer_elem_t *elem,*elemLFE;
snd_mixer_selem_id_t *sid;
if ((err = snd_mixer_open(&handle, 0)) < 0) {
error("Mixer %s open error: %s\n", card, snd_strerror(err));
return err;
}
if ((err = snd_mixer_attach(handle, card)) < 0) {
error("Mixer attach %s error: %s", card, snd_strerror(err));
snd_mixer_close(handle);
handle = NULL;
return err;
}
if ((err = snd_mixer_selem_register(handle, NULL, NULL)) < 0) {
error("Mixer register error: %s", snd_strerror(err));
snd_mixer_close(handle);
handle = NULL;
return err;
}
if ((err = snd_mixer_load(handle)) < 0) {
error("Mixer %s load error: %s", card, snd_strerror(err));
snd_mixer_close(handle);
handle = NULL;
return err;
}
snd_mixer_selem_id_alloca(&sid);
snd_mixer_selem_id_set_index(sid, 0);
snd_mixer_selem_id_set_name(sid, "Master");
elem = snd_mixer_find_selem(handle, sid);
snd_mixer_selem_id_set_name(sid, "LFE");
elemLFE = snd_mixer_find_selem(handle, sid);
for (;;) {
snd_mixer_wait(handle,-1);
snd_mixer_handle_events(handle);
snd_mixer_selem_get_playback_volume(elem, 1, &lval);
snd_mixer_selem_set_playback_volume(elemLFE, 0, lval);
snd_mixer_selem_get_playback_switch(elem, 1, &ival);
snd_mixer_selem_set_playback_switch(elemLFE, 0, ival);
}
snd_mixer_close(handle);
snd_mixer_free(handle);
return(0);
}
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