DosChgFilePtr

Bindings:  C, MASM 

This call moves the read/write pointer in accordance with the type of move 
specified. 

 DosChgFilePtr     (FileHandle, Distance, MoveType, NewPointer) 
 

 FileHandle (HFILE) - input 
    Handle returned by a previous DosOpen call. 

 Distance (LONG) - input 
    The offset to move, in bytes. 

 MoveType (USHORT) - input 
    Method of moving.  Specifies a location in the file from where 
    Distance to move the read/write pointer starts. Values and their 
    meanings are: 

    Value     Definition 
    0         Beginning of the file. 
    1         Current location of the read/write pointer. 
    2         End of the file. Use this method to determine a file's size. 
              

 NewPointer (PULONG) - output 
    Address of the new pointer location. 

 rc (USHORT) - return 
    Return code descriptions are: 

    0         NO_ERROR 
    1         ERROR_INVALID_FUNCTION 
    6         ERROR_INVALID_HANDLE 
 
 Remarks 

 The read/write pointer in a file is a signed 32-bit number. A negative 
 value moves the pointer backward in the file.  A positive value moves the 
 pointer forward. DosChgFilePtr cannot be used to seek to a negative 
 position in the file. 

 This call may not be used for a character device or pipe.