cannam@86: Error return codes possible from libvorbis and libvorbisfile:
cannam@86: 
cannam@86: All 'failure' style returns are <0; this either indicates a generic
cannam@86: 'false' value (eg, ready?  T or F) or an error condition.  Code can
cannam@86: safely just test for < 0, or look at the specific return code for more
cannam@86: detail.
cannam@86: 
cannam@86: *** Return codes:
cannam@86: 
cannam@86: OV_FALSE        The call returned a 'false' status (eg, ov_bitrate_instant 
cannam@86: 		can return OV_FALSE if playback is not in progress, and thus 
cannam@86: 		there is no instantaneous bitrate information to report.
cannam@86: 
cannam@86: OV_HOLE		libvorbis/libvorbisfile is alerting the application that 
cannam@86: 		there was an interruption in the data (one of: garbage 
cannam@86: 		between pages, loss of sync followed by recapture, or a 
cannam@86: 		corrupt page)
cannam@86: 
cannam@86: OV_EREAD        A read from media returned an error.
cannam@86: 
cannam@86: OV_EFAULT       Internal logic fault; indicates a bug or heap/stack 
cannam@86: 		corruption.
cannam@86: 
cannam@86: OV_EIMPL        The bitstream makes use of a feature not implemented in this 
cannam@86: 		library version.
cannam@86: 
cannam@86: OV_EINVAL       Invalid argument value.
cannam@86: 
cannam@86: OV_ENOTVORBIS	Bitstream/page/packet is not Vorbis data.
cannam@86: 
cannam@86: OV_EBADHEADER   Invalid Vorbis bitstream header.
cannam@86: 
cannam@86: OV_EVERSION	Vorbis version mismatch.
cannam@86: 
cannam@86: OV_ENOTAUDIO	Packet data submitted to vorbis_synthesis is not audio data.
cannam@86: 
cannam@86: OV_EBADPACKET	Invalid packet submitted to vorbis_synthesis.
cannam@86: 
cannam@86: OV_EBADLINK	Invalid stream section supplied to libvorbis/libvorbisfile, 
cannam@86: 		or the requested link is corrupt. 
cannam@86: 
cannam@86: OV_ENOSEEK	Bitstream is not seekable.
cannam@86: 
cannam@86: 
cannam@86: ****************************************************************
cannam@86: *** Libvorbis functions that can return failure/error codes:
cannam@86: 
cannam@86: int vorbis_analysis_headerout()
cannam@86:     OV_EIMPL
cannam@86: 
cannam@86: int vorbis_analysis_wrote()
cannam@86:     OV_EINVAL
cannam@86: 
cannam@86: int vorbis_synthesis_headerin()
cannam@86:     OV_ENOTVORBIS, OV_EVERSION, OV_EBADHEADER
cannam@86: 
cannam@86: int vorbis_synthesis()
cannam@86:     OV_ENOTAUDIO, OV_EBADPACKET
cannam@86: 
cannam@86: int vorbis_synthesis_read()
cannam@86:     OV_EINVAL
cannam@86: 
cannam@86: ****************************************************************
cannam@86: *** Libvorbisfile functions that can return failure/error codes:
cannam@86: 
cannam@86: int ov_open_callbacks()   
cannam@86:     OV_EREAD, OV_ENOTVORBIS, OV_EVERSION, OV_EBADHEADER, OV_FAULT
cannam@86: 
cannam@86: int ov_open()
cannam@86:     OV_EREAD, OV_ENOTVORBIS, OV_EVERSION, OV_EBADHEADER, OV_FAULT
cannam@86: 
cannam@86: long ov_bitrate()
cannam@86:     OV_EINVAL, OV_FALSE
cannam@86: 
cannam@86: long ov_bitrate_instant()
cannam@86:     OV_FALSE
cannam@86: 
cannam@86: ogg_int64_t ov_raw_total()
cannam@86:     OV_EINVAL
cannam@86: 
cannam@86: ogg_int64_t ov_pcm_total()
cannam@86:     OV_EINVAL
cannam@86: 
cannam@86: double ov_time_total()
cannam@86:     OV_EINVAL
cannam@86: 
cannam@86: int ov_raw_seek()
cannam@86:     OV_ENOSEEK, OV_EINVAL, OV_BADLINK
cannam@86: 
cannam@86: int ov_pcm_seek_page()
cannam@86:     OV_ENOSEEK, OV_EINVAL, OV_EREAD, OV_BADLINK, OV_FAULT
cannam@86: 
cannam@86: int ov_pcm_seek()
cannam@86:     OV_ENOSEEK, OV_EINVAL, OV_EREAD, OV_BADLINK, OV_FAULT
cannam@86: 
cannam@86: int ov_time_seek()
cannam@86:     OV_ENOSEEK, OV_EINVAL, OV_EREAD, OV_BADLINK, OV_FAULT
cannam@86: 
cannam@86: int ov_time_seek_page()
cannam@86:     OV_ENOSEEK, OV_EINVAL, OV_EREAD, OV_BADLINK, OV_FAULT
cannam@86: 
cannam@86: long ov_read()
cannam@86:     OV_HOLE, OV_EBADLINK