本来在使用mini2440进行录音后，再把录到得数据重新播放出来，会有噪声，但使用mini2440自带的录音测试程序则没有，请问是什么问题呢
播放程序测试过没问题的，就是录音那里出的问题

    求mini2440 linux2.6.32 进行录音操作的配置过程

arg = SIZE;
   status = ioctl(fd_dev_r, SOUND_PCM_WRITE_BITS, &arg);//设置量化位数
if (status == -1)
{
       perror("Cannot set SOUND_PCM_WRITE_BITS ");
       return 1;
}
arg = CHANNELS;
status = ioctl(fd_dev_r, SOUND_PCM_WRITE_CHANNELS, &arg);//设置声道数
if (status == -1)
   {
       perror("Cannot set SOUND_PCM_WRITE_CHANNELS");
       return 1;
   }
arg = RATE;
status = ioctl(fd_dev_r, SOUND_PCM_WRITE_RATE, &arg);//设置采样率
if (status == -1)
{
       perror("Cannot set SOUND_PCM_WRITE_WRITE");
       return 1;
}

//打开声卡设备，只写方式；并对声卡进行设置
fd_dev_w = open("/dev/dsp", O_WRONLY,0777);
if (fd_dev_w < 0)
{
       perror("Cannot open /dev/dsp device");
       return 1;
}
arg = SIZE;
status = ioctl(fd_dev_w, SOUND_PCM_WRITE_BITS, &arg);//设置量化位数
   if (status == -1)
{
      perror("Cannot set SOUND_PCM_WRITE_BITS ");
    return 1;
}
arg = CHANNELS;      
status = ioctl(fd_dev_w, SOUND_PCM_WRITE_CHANNELS, &arg);//设置声道数
if (status == -1)
{
    perror("Cannot set SOUND_PCM_WRITE_CHANNELS");
       return 1;
   }
arg = RATE;        
status = ioctl(fd_dev_w, SOUND_PCM_WRITE_RATE, &arg);//设置采样率
   if (status == -1)
{
       perror("Cannot set SOUND_PCM_WRITE_WRITE");
       return 1;
}

这个函数要怎么用？   我有函数但不知道怎么用，要编译嘛？编译时总说没有主函数通不过啊？  求助

呵呵  已经解决 楼上谢啦