[Overview][Constants][Types][Classes][Procedures and functions][Variables][Index] Reference for unit 'System' (#rtl)

Truncate

Truncate the file at position

Declaration

Source position: systemh.inc line 1293

procedure Truncate(

  var F: file

);

Description

Truncate truncates the (opened) file F at the current file position.

Errors

Depending on the state of the {$I} switch, a runtime error can be generated if there is an error. In the {$I-} state, use IOResult to check for errors.

See also

Append

  

Open a file in append mode

Filepos

  

Get position in file

Seek

  

Set file position

Example

Program Example71;

{ Program to demonstrate the Truncate function. }

Var F : File of longint;
    I,L : Longint;

begin
  Assign (F,'test.tmp');
  Rewrite (F);
  For I:=1 to 10 Do
    Write (F,I);
  Writeln ('Filesize before Truncate : ',FileSize(F));
  Close (f);
  Reset (F);
  Repeat
    Read (F,I);
  Until i=5;
  Truncate (F);
  Writeln ('Filesize after Truncate  : ',Filesize(F));
  Close (f);
end.

Documentation generated on: May 14 2021