Some embedded chip vendors forget to do this in their Linux Board Support Packages.
See 'feautre_test_macros(7)' for the details regarding defining the '_FILE_OFFSET_BITS=64' C preprocessor symbol.
Basically it causes the 'off_t' type in the C library to become 64 bits. ISO C and POSIX functions that uses 'off_t' include:
Google 'large file support' for more info.
ftruncate, lockf, lseek, pread, pwrite, truncate, fseek, ftello