2004.09.17 11:40 "Re: [Tiff] BigTIFF Tag Value Count issue", by Joris Van Damme

This does raise an interesting question. I would personally like libtiff to continue working on platforms with no identifiable 64bit integer data type if practical. Of course it would be fine if it only supported files smaller than 4GB in this case.

Does anyone know if stuff like PDA's and such have efficient-to-use 64bit integer datatypes? I am somewhat doubtful.

Is it allowable to have BigTIFF not work on those machines, but have classic TIFF still in working order? Perhaps a structure like...

#ifdef BIGTIFF_SUPPORT
if file is tiff classic {
#endif
  tiff classic supporting code
  ** this includes reporting error when suffering the consequences
       of getting a BigTIFF file **
#ifdef BIGTIFF_SUPPORT
} else {
  bigtiff supporting code
}
#endif

... when applied systematically, could solve this? Users without 64bit integer, could compile the library to support only TIFF classic, by disabling BIGTIFF_SUPPORT. If they should next use this TIFF-classic-only build to read a BigTIFF file, the file would be properly detected as not a valid TIFF, I presume (right from the start even, when looking at signature). Is this acceptable?

Joris Van Damme
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