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#### Seek

Declaration:
  Procedure Seek (Var F; Count : Longint);
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 (558) or Rewrite (559), 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:
  Eof (485), SeekEof (565), SeekEoln (566)

Listing: refex/ex56.pp

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.

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