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  Arguments
 
    file_variable    Typed, untyped, or text file; already assigned
 
    size             Optional; block size for data transfers; applies
                     only to untyped files (default is 128 bytes)
 
  Description
 
    The Reset procedure opens an existing file of any type or resets
    an open file. The opened file is the disk file or input device
    previously associated with file_variable. Use the Assign procedure
    to associate an external file name with file_variable. Reset moves
    the current position of the opened file to the first position in
    the file.
 
    A file can be text, typed, or untyped. Reset operates according to
    file type:
 
        Opens a text file for read-only. After Reset, the Eof function
        returns True if the file is empty and False otherwise. By
        default, Reset associates a 128-byte buffer with a text file.
        Use the SetTextBuf procedure to specify a buffer of a
        different size.
 
        Opens a typed or untyped file for reading and writing.
 
        Changes the default record size for untyped files. The
        BlockRead and BlockWrite procedures transfer data to and from
        untyped files in blocks (records) of a specific size. The
        FileSize function returns the size of a file in blocks. An
        untyped file has a default block size of 128 bytes. The size
        argument changes this setting. On many machines the most
        efficient size is a multiple of 512 bytes.
 
        Opens a device for input.
 
    To refer to the standard file Input (file handle 0), call Assign
    with a null string, then Reset the file.
 
    If file_variable has not been previously assigned to a external
    file name or if no external file by the associated name exists,
    an I/O error occurs.
 
    To prevent a program from halting with a run-time error when an
    I/O error occurs, turn off I/O checking with {$I-} and check the
    return value of the IOResult function.