2009.04.07 15:35 "Re: [Tiff] Writing tiff to in-memory buffer", by Bob Friesenhahn
Ok, my read function was wrong. Since I only want to write into the buffer the read procedure should return 0 and not the size read. Fixing that gives me a valid TIFF*. I also need to setup my seek_proc to prohibit it from seeking on an empty ostream. Doing though would raise the failbit. I don't understand why TIFFClientOpen is calling seek_proc( 0,0). It seems redundant to me.
Without thoroughly analyzing the code, (and making a WAG) I get the impression that libtiff reads back the header it just wrote to obtain the actual endianness of the data and the TIFF subformat.
It is also true that a write stream should be flushed before depending on data being in the file.
GraphicsMagick Maintainer, http://www.GraphicsMagick.org/