File Handling problem

[pampatipraveen]

Hi,

I have written ftp client using VB.
In this i used Get, Put and Seek statements for the local file handling when uploading and downloading. But these statements are not supporting the files larger than 2G.
I decided to use CreateFile, ReadFile and WriteFile apis. But in case of these api how to seek the file pointer to the perticular location in the file ?

Please help me

Regards
Praveenp

[hspc]

SetFilePointer , SetFilePointerEx APIs move the file pointer of an open file.

[pampatipraveen]

but will the setfileptr move the file positon more than 2GB ? because api has the long parameters...

i want to seek the file more than 2GB. is it ok with setfileptr?

thanking you

Praveenp

[hspc]

ok..
long (4 bytes=32bits) can not store more than 2GB number..
but note that SetFilePointer :
declaration :

DWORD SetFilePointer(
  HANDLE hFile,                // handle to file
  LONG lDistanceToMove,        // bytes to move pointer
  PLONG lpDistanceToMoveHigh,  // bytes to move pointer
  DWORD dwMoveMethod           // starting point
);

as you see it takes the second argument as the 32 Low-order 32 bits (unsigned) and the third argument is a Pointer to the high-order 32 of the 64-bit (the total is 64 bits=8bytes which can store much more than 2GB)...
So you can exceed 2GB by using this function
See MSDN for details

hope this can help

[pampatipraveen]

Ya, I got it . Thanks for the INformation.

I converted the 64 bit value into two 32-bit values and passed to the setfilepointer.

It works fine.

Thanks again.

Praveen