NAME

       roar_vs_stream - Set up stream parameters for VS object

SYNOPSIS

       #include <roaraudio.h>

       int roar_vs_stream(roar_vs_t * vss, const struct roar_audio_info * info, int dir, int * error);

DESCRIPTION

       This  function  asks  a  VS  object  opened by roar_vs_new_from_con(3) or roar_vs_new(3) to open the data
       connection using the audio parameters info and the stream direction dir.

       This function needs to be called before data is read or written if one of the above functions is used  to
       create the VS object.

       This  function  is  also  used  to  provide  parameters  for  the  file  mode  (which is started by using
       roar_vs_file(3) or roar_vs_file_simple(3)).  To play back a file this is not needed in a common  case  as
       the  VS  API  tries  to  find  correct  parameters.   It is required for all other stream directions. See
       roar_vs_file(3) and roar_vs_file_simple(3) for more information.

       On failture this function can be called again with different parameters.

PARAMETERS

       vss    The VS object to be updated.

       info   This is a pointer to the roar_audio_info structure  storing  the  audio  format  parameters.   The
              structure  contains  the  following  members: rate (sample rate), bits (bits per sample), channels
              (channels per frame) and codec.

       dir    This is  the  stream  direction.  Common  values  include  ROAR_DIR_PLAY  for  waveform  playback,
              ROAR_DIR_MONITOR  for  waveform  monitoring,  ROAR_DIR_RECORD  for  waveform  recording.  For MIDI
              ROAR_DIR_MIDI_IN and ROAR_DIR_MIDI_OUT is used.

       error  This is a pointer to a integer used to store the error value in case of error.  This can  be  NULL
              if  not  used  but it is very recommended to use this error value to report good error messages to
              the user.

RETURN VALUE

       On success these calls return 0.  On error, -1 is returned.

EXAMPLES

        struct roar_audio_info info;
        int err;

        if ( roar_profile2info(&info, "isdn-eu") == -1 ) {
         // error handling.
        }

        if ( roar_vs_stream(vss, &info, ROAR_DIR_PLAY, &err) == -1 ) {
         // error handling.
        }

SEE ALSO

       roar_vs_file(3), roar_vs_file_simple(3), roarvs(7), libroar(7), RoarAudio(7).