Bdtjtk

I"m trying to write raw data i get externally from serial port to the sound card device using c code in ubuntu in order to play it.

I"ve looked everywhere for a solution and found that it can be done via ALSA API, but couldn't fund any clear example on how should i do it.
I also tried using the ioctl() function - but it doesn't play.

#include <stdio.h>

#include <fcntl.h>  // File Control Definitions 

#include <string.h>

#include <pthread.h>

#include <semaphore.h> 

#include <stdlib.h>

#include <termios.h>

#include <unistd.h>

#include <sys/ioctl.h>

#include <linux/kd.h>

int flg = 0, rdlen = 0;

int com_ptr, sound_ptr;

char input_data[16];

char output_data[16];

sem_t data_mutex; 





void* read_data(void *arg)

{

    int i, j;



    for (j = 0 ; j < 5 ; j++)

    {

        while(flg == 1);//waits for the data to be read

        sem_wait(&data_mutex);

        printf("ndata_read_mutex MUTEX TAKENn");

        printf("readn");



        rdlen = read(com_ptr, input_data, sizeof(input_data));

        //fwrite(buf, 1, rdlen, log_file);

        printf("input length : %dn",rdlen);



        for(i = 0 ; i < rdlen - 1; i++)

        {

            //input_data[i] = data[i];

            printf("Reading.... : %cn", input_data[i]);

        }//for



        if(sem_post(&data_mutex))

        {

            printf("ERROR POSTING data_mutexn");

        }//if

        else

        {

            flg = 1;

            printf("data_mutex WAS POSTEDn");

        }

    }//for

}//read_data



void* play_data(void *arg)

{

    int i, j;



    for (j = 0 ; j < 5 ; j++)

    {

        while (flg == 0);// waits for the data to be redy

        sem_wait(&data_mutex);

        printf("ndata_ready_mutex MUTEX TAKENn");

        printf("playn");



        for(i = 0 ; i < rdlen - 1; i++)

        {

            output_data[i] = input_data[i];

            printf("Playing.... : %cn", output_data[i]);

            //rdlen = write(sound_ptr, input_data, sizeof(input_data));

            //ioctl(sound_ptr, KIOCSOUND, 119);

            //usleep(500000);

            //sound(output_data[i] - 48);

        }//for



        if(sem_post(&data_mutex))

        {

            printf("ERROR POSTING data_mutexn");

        }//if

        else

        {

            flg = 0;

            printf("data_mutex WAS POSTEDn");

        }

    }//for

}//play_data



int main(int argc, char **argv)

{

    int i;



    sem_init(&data_mutex, 0, 1); 



    void * read_return, *play_return;

    pthread_t play_t, read_t;







    if (argc == 3)

    {

        printf( "input address = %sn", argv[1]);

        printf( "output address = %sn", argv[2]);

    }





    com_ptr = open("/dev/stdin", O_RDWR | O_NOCTTY);

    sound_ptr = open("/proc/asound/card0", 'w');

    if(com_ptr == -1)

        printf("nError! in Opening ttyUSB0  ");

    else

        printf("nttyUSB0 Opened Successfully ");





    if (pthread_create(&read_t, NULL, &read_data, NULL))

    {

        perror("read pthread_create() error");

        exit(1);

    }//if



    sleep(1); // ensuring the read gets the first round



    if (pthread_create(&play_t, NULL, &play_data, NULL))

    {

        perror("play pthread_create() error");

        exit(1);

    }//if



    if (pthread_join(read_t, &read_return))

    {

        perror("read pthread_join() error");

        exit(1);

    }//if

    if (pthread_join(play_t, &play_return))

    {

        perror("play pthread_join() error");

        exit(1);

    }//if



    sem_destroy(&data_mutex); 



    return 0;

}//main

I'm getting the data and can read it - but I need to write it to the sound card - which i can't do.