Solved

interacting with DOS

Posted on 2001-07-21
5
258 Views
Last Modified: 2010-04-06
Hi.  How does one interact with DOS from Delphi/Pascal.  I want to (for example) be able to interact with a program run externally (by e.g WinExec), and do different things based on its output.

1) run dos command using winexec
THEN
if *this* happens, do this
if *that* happens, do this,
so my question is basically how to do this - how can I use Delphi to read the output of another program run in e.g DOS?

Thanks for the help
0
Comment
Question by:Lmoen
5 Comments
 
LVL 22

Accepted Solution

by:
Mohammed Nasman earned 120 total points
ID: 6304607
Hello

  here's an example to how capture the dos output, this will add the  output for the chkdsk to memo

//=====
{
The example runs 'chkdsk.exe c:\' and displays the output to Memo1

Put a TMemo (Memo1) and a TButton (Button1) in your form
Put this code in the OnCLick of Button1:
}

procedure TForm1.Button1Click(Sender: TObject);

 procedure RunDosInMemo(DosApp:String;AMemo:TMemo);
 const
    ReadBuffer = 2400;
 var
  Security            : TSecurityAttributes;
  ReadPipe,WritePipe  : THandle;
  start               : TStartUpInfo;
  ProcessInfo         : TProcessInformation;
  Buffer              : Pchar;
  BytesRead           : DWord;
  Apprunning          : DWord;
 begin
  With Security do begin
   nlength              := SizeOf(TSecurityAttributes);
   binherithandle       := true;
   lpsecuritydescriptor := nil;
  end;
  if Createpipe (ReadPipe, WritePipe,
                 @Security, 0) then begin
   Buffer  := AllocMem(ReadBuffer + 1);
   FillChar(Start,Sizeof(Start),#0);
   start.cb          := SizeOf(start);
   start.hStdOutput  := WritePipe;
   start.hStdInput   := ReadPipe;
   start.dwFlags     := STARTF_USESTDHANDLES +
                        STARTF_USESHOWWINDOW;
   start.wShowWindow := SW_HIDE;

   if CreateProcess(nil,
          PChar(DosApp),
          @Security,
          @Security,
          true,
          NORMAL_PRIORITY_CLASS,
          nil,
          nil,
          start,
          ProcessInfo)
   then
   begin
    repeat
     Apprunning := WaitForSingleObject
                  (ProcessInfo.hProcess,100);
     Application.ProcessMessages;
    until (Apprunning <> WAIT_TIMEOUT);
     Repeat
       BytesRead := 0;
       ReadFile(ReadPipe,Buffer[0],
                 ReadBuffer,BytesRead,nil);
       Buffer[BytesRead]:= #0;
       OemToAnsi(Buffer,Buffer);
       AMemo.Text := AMemo.text + String(Buffer);
     until (BytesRead < ReadBuffer);
  end;
  FreeMem(Buffer);
  CloseHandle(ProcessInfo.hProcess);
  CloseHandle(ProcessInfo.hThread);
  CloseHandle(ReadPipe);
  CloseHandle(WritePipe);
  end;
 end;

 begin {button 1 code}
   RunDosInMemo('chkdsk.exe c:\',Memo1);
 end;
 
Best regards
Mohammed Nasman
0
 

Expert Comment

by:teacher_mod
ID: 6305243
Irrelevant and offensive comments have been deleted from this Question by:

teacher_mod
Community Support Moderator
Experts-Exchange
teacher_mod@experts-exchange.com
0
 

Expert Comment

by:juncanonigox
ID: 8867403
hi,

i've just implemented the above code named "RunDosInMemo" in my app, and it works fine when the DOS prog returns something but it hangs up when it does not return anything.  

the DOS outputs depends on the parameter being passed when called.

is there a way to determine if the DOS prog does not return anything?

thanks.
--juncanonigo
0

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Introduction The parallel port is a very commonly known port, it was widely used to connect a printer to the PC, if you look at the back of your computer, for those who don't have newer computers, there will be a port with 25 pins and a small print…
In this tutorial I will show you how to use the Windows Speech API in Delphi. I will only cover basic functions such as text to speech and controlling the speed of the speech. SAPI Installation First you need to install the SAPI type library, th…
This is used to tweak the memory usage for your computer, it is used for servers more so than workstations but just be careful editing registry settings as it may cause irreversible results. I hold no responsibility for anything you do to the regist…
Internet Business Fax to Email Made Easy - With eFax Corporate (http://www.enterprise.efax.com), you'll receive a dedicated online fax number, which is used the same way as a typical analog fax number. You'll receive secure faxes in your email, fr…

920 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

16 Experts available now in Live!

Get 1:1 Help Now