Finding all the devices I can use to play PCM with ALSA

I think you can use snd_device_name_hint for enumerating devices.Here is an example. Beware that I haven't compiled it !

char **hints;/* Enumerate sound devices */int err = snd_device_name_hint(-1, "pcm", (void***)&hints);if (err != 0)   return;//Error! Just returnchar** n = hints;while (*n != NULL) {    char *name = snd_device_name_get_hint(*n, "NAME");    if (name != NULL && 0 != strcmp("null", name)) {        //Copy name to another buffer and then free it        free(name);    }    n++;}//End of while//Free hint buffer toosnd_device_name_free_hint((void**)hints);

It was my first requirements to a linux/unix projects where I need to know about all of the available audio devices capability and name. Then I need to use these devices to capture and plaback the audio. What I have done is pretty simple. There is a linux/unix command which is used to find the devices through alsa utility in linux.

It is:

aplay -l

Now what I did is just make a programme to give the out as like as this by alsa.

For everyone's help I have made a (.so) library and a sample Application demonstrating the use of this library in c++.

The output of my library is like-

[root@~]# ./IdeaAudioEngineTestHDA Intel plughw:0,0HDA Intel plughw:0,2USB Audio Device plughw:1,0

This library can also capture and playback the real-time audio data.

It is available with documentation in IdeaAudio library with Duplex Alsa Audio

Just for grins, your program reformatted:

#include <stdio.h>#include <limits.h>#include <stdlib.h>#include <unistd.h>#include <alsa/asoundlib.h>void listdev(char *devname){    char** hints;    int    err;    char** n;    char*  name;    char*  desc;    char*  ioid;    /* Enumerate sound devices */    err = snd_device_name_hint(-1, devname, (void***)&hints);    if (err != 0) {        fprintf(stderr, "*** Cannot get device names\n");        exit(1);    }    n = hints;    while (*n != NULL) {        name = snd_device_name_get_hint(*n, "NAME");        desc = snd_device_name_get_hint(*n, "DESC");        ioid = snd_device_name_get_hint(*n, "IOID");        printf("Name of device: %s\n", name);        printf("Description of device: %s\n", desc);        printf("I/O type of device: %s\n", ioid);        printf("\n");        if (name && strcmp("null", name)) free(name);        if (desc && strcmp("null", desc)) free(desc);        if (ioid && strcmp("null", ioid)) free(ioid);        n++;    }    //Free hint buffer too    snd_device_name_free_hint((void**)hints);}int main(void){    printf("PCM devices:\n");    printf("\n");    listdev("pcm");    printf("MIDI devices:\n");    printf("\n");    listdev("rawmidi");    return 0;}