Vorbis dev - Nov 2005 - predictability of buffer size for decoding

I am wondering if buffer size for my decoding to pcm can be predicted dependably
as follows.  So far, the one problem I have had is when I have played a file of
only about 5k.  The buffer was a little less than 10% too small.  I
"solved" that by padding the result with an extra 20 percent. 
However, I have been told that I should be able to rely on the value of
ov_pcm_total.

 char* m_pDataVorbis;
 . . .
 OggVorbis_File vf;
 . . .
 vorbis_info* vi = ov_info(&vf,-1);
 . . .
int pcmTotal = ov_pcm_total(&vf, -1);
m_pDataVorbis =  new char[pcmTotal * vi->channels * 2];
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On 11/1/05, Steve Russell <srussell@innernet.net>
wrote:
>
> I am wondering if buffer size for my decoding to pcm can be predicted
> dependably as follows.  So far, the one problem I have had is when I have
> played a file of only about 5k.  The buffer was a little less than 10% too
> small.  I "solved" that by padding the result with an extra 20
percent.
> However, I have been told that I should be able to rely on the value of
> ov_pcm_total.
Yes, ov_pcm_total will return sample-accurate accurate values for a
valid ogg stream.

It's possible to create files that will confuse it into returning the
wrong values, but those would be rare (and invalid), so I wouldn't
worry about them. Just check that you don't overrun the buffer you DID
allocate.

Mike

----- Original Message ----- 
From: "Michael Smith" <msmith@xiph.org>
I don't know what might be going wrong. Can you run the
vorbisfile_example program on this file on your system (from
vorbis/examples/ in the libvorbis source code)? Run like
"./vorbisfile_example < input.ogg > output.raw", it should print
out
some info about the file - including the number of samples according
to vorbisfile, and then write that many samples (as 16 bit data) to
the output file.

This works fine on my system.

Mike
---------
Shortly after the vorbisfile_example.exe command prompt window opens, I get 
this:

NTDLL! 7c918fea()
NTDLL! 7c90104b()
fseek(_iobuf * 0x00422a30 __iob, long 0, int 1) line 103 + 9 bytes
VORBISFILE_D! 10002937()
VORBISFILE_D! 1000141d()
VORBISFILE_D! 10001399()
VORBISFILE_D! 100028ca()
main() line 49 + 21 bytes

which leads me to here:

  if(ov_open(stdin, &vf, NULL, 0) < 0) {

Any thought on how to proceed?