QUOTE(jcoalson @ May 5 2008, 13:45)

this question is better directly to the flac-dev mailing list. also, there's not enough information to debug with. first check the return value of FLAC__stream_encoder_init_file()
In fact, i've posted this same question directly to the flac-dev mailing list with no results. It is obvious that this kind of troubles by programming the flac code are not remarkables for most flac developpers that they are so busy looking for new advances in encoding.
Finally i could resolve my problem with that function with no support.