On the IA-32 (read: Intel) architecture, all Linux filesystems starting in the 2.4 series support 64-bit file sizes. Note that in POSIX, open() only uses 32-bit file sizes, so C code has to use a different function (open64(), IIRC). My guess is that your decompression program is using the older version of open(), which you should be able to fix by getting a new version to compile (assuming its one of the common Free Software compressors, like gzip or bzip2).

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I wanted to explore how Perl's closures can be manipulated, and ended up creating an object system by accident.
-- Schemer

Note: All code is untested, unless otherwise stated