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  Argument
 
    file_variable    File of type text
 
  Description
 
    The AssignCrt procedure associates a file variable of type text
    with the console. After a successful assignment and subsequent call
    to Reset or Rewrite, all operations directed to file_variable
    act directly on the CRT monitor. This gives an advantage in speed.
    Use AssignCrt to associate I/O with the console when standard I/O is
    being redirected to a file or to get faster output to the screen.
 
    Use AssignCrt to associate either input or output with the console
    when the standard file Input or Output has been redirected to a
    file. When the Crt unit is used, it assigns I/O to the Crt and
    removes the ability to redirect I/O with the DOS redirection
    operators (<) and (>). However, if redirection of input is
    reenabled (by calling the Assign procedure), no input can come from
    the keyboard. Likewise, if output is redirected, no output goes to
    the screen. AssignCrt can reenable either input from the keyboard
    or output to the screen:
 
        To read from the keyboard while input is redirected from a
        file, call AssignCrt and Reset for file_variable. Then Read
        from file_variable.
 
        To write to the screen while output is redirected to a file,
        call AssignCrt and Rewrite for file_variable. Then Write to
        file_variable.
 
    Use AssignCrt to get faster output to the screen. If output has not
    been redirected, standard output is the CRT. Write and Writeln send
    text to the screen. AssignCrt in this situation gives an advantage
    of speed. The Crt unit's direct-video routines are fast because
    they bypass DOS and deal directly with the BIOS or the CRT
    controller. The disadvantage of using AssignCrt is some loss of
    portability.
 
    If AssignCrt is passed a file_variable already associated with an
    open file, the previous file assignment is lost.