I am running into integer overflow using the standard ftell and fseek options inside of G++, but I guess I was mistaken because it seems that ftell64 and fseek64 are not available. I have been searching and many websites seem to reference using lseek with the off64_t datatype, but I have not found any examples referencing something equal to fseek. Right now the files that I am reading in are 16GB+ CSV files with the expectation of at least double that.
Without any external libraries what is the most straightforward method for achieving a similar structure as with the fseek/ftell pair? My application right now works using the standard GCC/G++ libraries for 4.x.
fseek64 is a C function. To make it available you'll have to define _FILE_OFFSET_BITS=64 before including the system headers That will more or less define fseek to be actually fseek64. Or do it in the compiler arguments e.g. gcc -D_FILE_OFFSET_BITS=64 ....
http://www.suse.de/~aj/linux_lfs.html has a great overviw of large file support on linux: