Hi All, Please find that the file operations fseek and ftell fail for files more than 2 gb. There are system calls _fseeki64 and _ftelli64 to support more than 2 gb in VC8. But there are no such APIs in VC6. The same functionalities are provided by _lseeki64 and _telli64 system calls in VC6. But these are low level I/O routines, which require a file handle obtained by another low level routine(_open). Moreover, Not all the functionalities of buffered I/O are provided by non - buffered I/O. Please let me know,Is there any other better solution to support files more than 2 gb using system calls availbale in VC6. Thanks in Advance!!