Get Large File Size in C
Before anyone complains of "duplicate", I've been checking SO quite thoroughly, but there seem to be no clean answer yet, although the question looks quite simple.
I'm looking for a portable C code, which is able to provide the size of a file, even if such a file is bigger than 4GB.
The usual method (fseek, ftell) works fine, as long as the file remains < 2GB. It's fairly well supported everywhere, so I'm trying to find something equivalent.
Unfortunately, the updated methods (fseeko, ftello) are not supported by all compilers. For example, MinGW miss it (and obviously MSVC). Furthermore, some comments make me believe that the new return type (off_t) does not necessarily support size > 2GB, it may depend on some external parameters, to be checked.
The unambiguous methods (fseeko64, ftello64) are not supported by MSVC. MS provides their equivalent, _fseeki64 & _ftelli64. This is already bad, but it becomes worse : some Linux configurations seem to badly support these functions during run time. For example, my Debian Squeeze on PowerPC, using GCC 4.4, will produce a "filesize" method using fseeko64 which always return 0 (while it works fine for Ubuntu64). MinGW seems to answer some random garbage above 2GB.
Well, I'm a bit clueless as far as portability is concerned. And if I need to make a bunch of #if #else, then why not go straight to the OS & compilers specifics methods in the first place, such as GetFileSize() for MSVC for example.
Answer
You said it: there's no portable method; if I were you I'd just go with GetFileSize on Windows and stat on POSIX.