EInOutError Class

EInOutError is the exception class for file input/output errors.

Pascal

EInOutError = class(Exception);

C++

class EInOutError : public Exception;

File

SysUtils

Description

EInOutError is raised when an file input/output error occurs, provided I/O checking is enabled.

Note: In Delphi code, use the $I+ directive to enable I/O checking. If an I/O error occurs while this directive is disabled, the application must call IOResult to clear the error.

Note: In C++ programs, I/O checking is a project option.

The error code is available in the ErrorCode class member. Error codes are come in ranges: 0-99 (native OS errors)

Error codes in the range 0-99 represent OS error conditions, which are different for Windows and Linux. Refer to the OS documentation for complete error summaries. The SysErrorMessage function returns descriptive text for OS errors.

Here are some common OS I/O errors, arranged by rough equivalents in Linux and Windows:

LinuxWindows

Linux		Windows
Error Code	Description	Error Code	Description
2	No such file or directory	2	File not found
3	Path not found
5	I/O Error
13	Permission denied	5	Access denied
20	Not a directory
21	Is a directory
32	Sharing violation
Error codes in the range 100 to 149 represent error conditions raised by CLX. Here are the CLX I/O error codes:

Error code	Meaning
100	End of File
101	Disk Full
102	File variable not assigned
103	File not open
104	File not open for input
105	File not open for output
106	Error in formatted input
107	File already open

Delphi Examples:

Copy Code

{
Click the button to open a TOpenDialog, then select a file 
to delete.
}

procedure TForm1.Button1Click(Sender: TObject);
var
  F: Textfile;
begin
  OpenDialog1.Title := 'Delete File';
  if OpenDialog1.Execute then
  begin
    AssignFile(F, OpenDialog1.FileName);
    try
      Reset(F);
      if MessageDlg('Erase ' + OpenDialog1.FileName + '?',
        mtConfirmation, [mbYes, mbNo], 0) = mrYes then
      begin
        CloseFile(F);
        Erase(F);
      end;
    except
      on EInOutError do
        MessageDlg('File I/O error.', mtError, [mbOk], 0);
    end;
  end;
end;