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Reset procedure

In unit System

Open file for reading.

Declaration

pascal
procedure Reset(var f: File; l: LongInt)

Description

Reset opens a file F for reading. F can be any file type. If F is a text file, or refers to standard I/O (e.g : '') then it is opened read-only, otherwise it is opened using the mode specified in filemode.

If F is an untyped file, the record size can be specified in the optional parameter L. A default value of 128 is used.

File sharing is not taken into account when calling Reset.

Note that the path can be only 255 characters long.

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

Example: ex51

pascal
Program Example51;

{ Program to demonstrate the Reset function. }

Function FileExists (Name : String) : boolean;

Var F : File;

begin
  {$i-}
  Assign (F,Name);
  Reset (F);
  {$I+}
  FileExists:=(IoResult=0) and (Name<>'');
  if FileExists then
    Close (f);
end;

begin
  If FileExists (Paramstr(1)) then
    Writeln ('File found')
  else
    Writeln ('File NOT found');
end.

An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.