#include "vocal.h" int init_dsp( char *device ) { int dsp, arg; char *dev = (device == NULL ? "/dev/dsp" : device); if ((dsp=open( dev, O_RDONLY)) < 0) { perror("open of sound device failed"); return -1; } arg = AFMT_U8; if (ioctl(dsp, SNDCTL_DSP_SETFMT, &arg)<0) { perror ("SNDCTL_DSP_SETFMT failed"); return -1; } if (arg != AFMT_U8) { perror ("sound device doesn't support AFMT_U8"); return -1; } arg = SIZE; if (ioctl(dsp, SOUND_PCM_WRITE_BITS, &arg) == -1) { perror("SOUND_PCM_WRITE_BITS ioctl failed"); return -1; } if (arg != SIZE) { perror("unable to set sample size"); return -1; } arg = CHANNELS; if (ioctl(dsp, SOUND_PCM_WRITE_CHANNELS, &arg) == -1) { perror("SOUND_PCM_WRITE_CHANNELS ioctl failed"); return -1; } if (arg != CHANNELS) { perror("unable to set number of channels"); return -1; } arg = RATE; if (ioctl(dsp, SOUND_PCM_WRITE_RATE, &arg) == -1) { perror("SOUND_PCM_WRITE_WRITE ioctl failed"); return -1; } return dsp; }