[fpc-pascal]files handler in FPC

[Adam Naumowicz]

On 6 Mar 2002, [iso-8859-2] £ukasz Le¶niak wrote:

> procedure ReadDataFromFile(var s: SetOfperson)
> var i, F: LongInt;
>     p: SetOfPerson;
>  .
> .
>  i:=0;
>  F:=FileOpen(path_to_F, fmOpenRead);
>  if F = -1 then Halt(1);
>  new(p);
>  FileSeek(F, i, fsFromBeginning);
>  FileRead(F, p^.desc, SizeOf(p^.desc));
>  (* XXX *)
>  p^.next:=s;
>  s:=p;
>  i:= i + 1;
>  end;

Even if you have a loop there is still one more thing:
if you want to read the file sequentially there is no need to set the file
position with FileSeek since FileRead changes the current position. But
anyway, if you read a raw data type (as in this case) you should increment
the position by SizeOf buffer, not by 1.

Best regards,
Adam Naumowicz

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