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

# Reset

Open file for reading

## Declaration

Source position: systemh.inc line 1273

`procedure Reset(`
`var f: file;`
`l: LongInt`
`); procedure Reset(`
`var f: file`
`); procedure Reset(`
`var f: TypedFile`
`); procedure Reset(`
`var t: Text`
`);`

## 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

Rewrite |  | Open file for writing
Assign |  | Assign a name to a file
Close |  | Close a file
Append |  | Open a file in append mode
FileMode |  | Default file mode for untyped files.

## Example

    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.

Documentation generated on: May 14 2021