From: "Peter Below (TeamB)" <100113.1101@compuXXserve.com>
Subject: Re: Deleting all files on a floppy
Date: 24 Apr 1999 00:00:00 GMT
Message-ID: <VA.00002c56.00e46067@petersnewbox>
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References: <372097D6.E98315A1@profitsys.sk.ca>
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In article <372097D6.E98315A1@profitsys.sk.ca>, David Heagy wrote:
> I need to delete all files on a floppy (including directories) in delphi
> 1. Does anyone know how?
>

The fastest way is in fact to perform a quick format on the diskette.
Since there is no simple API to do that available you simply WinExec
format:

  Winexec('format.com A: /Q', SW_SHOW );

However, this forces the user to respond to the prompts format issues.
You can prevent this by preparing two files. The first is a response file
that contains the answers to the prompts: two empty lines and one line
with a 'n' in it:

  Procedure WriteResponsefile;
  Var
    f: System.Text;
  Begin
    System.Assign( f, 'resp.txt' );
    Rewrite(f);
    WriteLn(f);
    WriteLn(f);
    WriteLn(f,'n');
    System.Close( f );
  End;

The second is a batch file that you then launch:

  Procedure Quickformat_Drive_A;
  Const
    batch = 'qf_a.bat';
  Var
    f: System.Text;
  Begin
    WriteResponseFile;
    System.Assign( f, batch );
    Rewrite(f);
    WriteLn(f, 'format A: /Q < resp.txt' );
    WriteLn(f, 'del resp.txt' );
    Write( f, 'del %0' );  { Note: no newline! }
    System.Close(f);
    WinExec( batch, SW_HIDE );
  End;

This uses the "self-immolating batchfile" approach <g>. A batch can delete
itself, different from a running EXE. The files are generated in whatever
happens to be the current directory. It would probably be smart to set
that to the windows TEMP directory first, that is guaranteed to be
writeable.

I tested this with D3/Win95B (no D1 on this crate). I don't remember if
the Win 3.1 WinExec was smart enough to execute batch files, you may have
to get the command interpreter from the COMSPEC environment variable (see
getEnvVar in windos.pas, copy this routine, do not use the unit!) and
execute that with a commandline of '/C '+batch.

Peter Below (TeamB)  100113.1101@compuserve.com)
No e-mail responses, please, unless explicitely requested!