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    Seek

    Set file position.

    Declaration

    Source position: systemh.inc line 1468

    procedure Seek(var f: File; Pos: Int64);

    Description

    Seek sets the file-pointer for file F to record Nr. Count. The first record in a file has Count=0. F can be any file type, except Text. If F is an untyped file, with no record size specified in Reset or Rewrite, 128 is assumed.

    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

    Name Description
    Eof Check for end of file.
    SeekEof Set file position to end of file.
    SeekEoln Set file position to end of line.

    Example

    Program Example56;

{ Program to demonstrate the Seek function. }

Var
  F : File;
  I,j : longint;

begin
  { Create a file and fill it with data }
  Assign (F,'test.tmp');
  Rewrite(F); { Create file }
  Close(f);
  FileMode:=2;
  ReSet (F,Sizeof(i)); { Opened read/write }
  For I:=0 to 10 do
    BlockWrite (F,I,1);
  { Go Back to the begining of the file }
  Seek(F,0);
  For I:=0 to 10 do
    begin
    BlockRead (F,J,1);
    If J<>I then
      Writeln ('Error: expected ' ,i,', got ',j);
    end;
  Close (f);
end.