cannam@86: This partially opens a vorbis file to test for Vorbis-ness. It loads
cannam@86: the headers for the first chain and tests for seekability (but does not seek).
cannam@86: Use ov_test_open() to finish opening the file
cannam@86: or ov_clear to close/free it.
cannam@86:
cannam@86:
cannam@86:
WARNING for Windows developers: Do not use ov_test()
cannam@86: in Windows applications; Windows linking places restrictions on
cannam@86: passing FILE * handles successfully, and ov_test() runs afoul
cannam@86: of these restrictions [a] in exactly the same
cannam@86: way as ov_open(). See the ov_test_callbacks() page for
cannam@86: details on using ov_test_callbacks() instead.
cannam@86:
cannam@86:
cannam@86:
cannam@86:
cannam@86:
cannam@86:
cannam@86: int ov_test(FILE *f,OggVorbis_File *vf,char *initial,long ibytes);
cannam@86:
cannam@86:
cannam@86:
cannam@86:
cannam@86:
cannam@86:
Parameters
cannam@86:
cannam@86:
f
cannam@86:
File pointer to an already opened file
cannam@86: or pipe (it need not be seekable--though this obviously restricts what
cannam@86: can be done with the bitstream).
cannam@86:
vf
cannam@86:
A pointer to the OggVorbis_File structure--this is used for ALL the externally visible libvorbisfile
cannam@86: functions. Once this has been called, the same OggVorbis_File
cannam@86: struct should be passed to all the libvorbisfile functions.
cannam@86:
initial
cannam@86:
Typically set to NULL. This parameter is useful if some data has already been
cannam@86: read from the file and the stream is not seekable. It is used in conjunction with ibytes. In this case, initial
cannam@86: should be a pointer to a buffer containing the data read.
cannam@86:
ibytes
cannam@86:
Typically set to 0. This parameter is useful if some data has already been
cannam@86: read from the file and the stream is not seekable. In this case, ibytes
cannam@86: should contain the length (in bytes) of the buffer. Used together with initial
cannam@86:
cannam@86:
cannam@86:
cannam@86:
Return Values
cannam@86:
cannam@86:
0 for success
cannam@86:
cannam@86:
less than zero for failure:
cannam@86:
cannam@86:
OV_EREAD - A read from media returned an error.
cannam@86:
OV_ENOTVORBIS - Bitstream contains no Vorbis data.
cannam@86:
OV_EVERSION - Vorbis version mismatch.
cannam@86:
OV_EBADHEADER - Invalid Vorbis bitstream header.
cannam@86:
OV_EFAULT - Internal logic fault; indicates a bug or heap/stack corruption.
cannam@86:
cannam@86:
cannam@86:
cannam@86:
cannam@86:
Notes
cannam@86:
cannam@86: All the notes from ov_open() apply to ov_test().
cannam@86:
cannam@86: