FS_FileSeek( PIOREQ pir )
The current file position is set or obtained through FS_FileSeek. This routine handles the Win32 function GetFileSize(); and INT 21h functions: 23h, and 42h.
ir_rh
Supplies handle to disk volume or network resource which contains the file.
ir_fh
Supplies FSD file handle.
ir_sfn
Supplies system file number.
ir_flags
Supplies the type of seek method to perform.
Seek Method Values: One of the following seek methods will be specified. | |
Value | Meaning |
FILE_BEGIN | Position is an absolute offset from the beginning of the file. |
FILE_END | Position is a signed offset relative to the end of the file. |
ir_pos
Supplies the file seek offset.
ir_user
Supplies user id for this request.
ir_pid
Supplies process id for this request.
ir_error | Returns status of the operation ( 0 if no error, errorcode otherwise ). |
ir_pos | Returns the current file position. |
The FILE_BEGIN method is provided as an optimization only and may otherwise be ignored. The idea is simply to allow the FSD to do read-ahead based on this information if it chooses to. There is no guarantee that file I/O will take place at the passed file position however.