Solved

Process.Exitcode returns wrong value

Posted on 2013-11-15
6
521 Views
Last Modified: 2013-11-19
I've written a C# class that calls a DOS application in the context of a Process. The problem is that Process.Exitcode always returns 0 indicating success even if the DOS program fails. I've run this DOS application in a batch file from a command prompt, and I know it returns an error code. Here's my setup for the process:

        public void Start()
        {
            m_isDone = false;
            m_result = 0;
            m_isStandardOutputDone = false;
            m_isErrorOutputDone = false;
            m_consoleProcess = new Process();
            m_consoleProcess.StartInfo.FileName = m_command;
            m_consoleProcess.StartInfo.Arguments = m_commandArguments;
            m_consoleProcess.StartInfo.UseShellExecute = false;
            m_consoleProcess.StartInfo.CreateNoWindow = true;
            m_consoleProcess.StartInfo.RedirectStandardOutput = true;
            m_consoleProcess.StartInfo.RedirectStandardError = true;
            m_consoleProcess.OutputDataReceived += StandardOutputEventHandler;
            m_consoleProcess.ErrorDataReceived += ErrorOutputEventHandler;
            m_consoleProcess.Start();
            m_consoleProcess.BeginOutputReadLine();
            m_consoleProcess.BeginErrorReadLine();
        }

And the standard output event handler:

        private void StandardOutputEventHandler(object sendingProcess, DataReceivedEventArgs eventArgs)
        {
            String output = eventArgs.Data;
            if ( !String.IsNullOrEmpty(output) )
            {
                // Notify standard output event subscribers that there's new text.
                StandardOutputEvent(this, eventArgs);
            }
            else
            if ( (output == null) && m_consoleProcess.HasExited )
            {
                m_isStandardOutputDone = true;

                if ( m_isErrorOutputDone && !m_isDone )
                {
                    // Signal process completion.
                    m_isDone = true;
                    m_result = m_consoleProcess.Exitcode;
                    EventArgs e = new EventArgs();
                    if ( ProcessDoneEvent != null )
                    {
                        ProcessDoneEvent(this, e);
                    }
                }
            }
        }

It's here in the standard output event handler that I determine whether the process has completed and record the exit code. This works well, except that the exit code doesn't represent the correct output of the DOS program. How do I obtain the correct exit code?
0
Comment
Question by:alconlabs
  • 3
  • 2
6 Comments
 
LVL 96

Expert Comment

by:Bob Learned
ID: 39653357
It doesn't look like you are waiting for the process to end, so the ExitCode won't be set yet.
0
 

Author Comment

by:alconlabs
ID: 39653940
m_consoleProcess.HasExited is true, so I assume the process has ended. The documentation for HasExited would seem to imply that if HasExited is true, it's safe to query the ExitCode and ExitTime properties, no?
0
 
LVL 96

Accepted Solution

by:
Bob Learned earned 500 total points
ID: 39653964
As a test, you can try Process.WaitForExit, and see if the ExitCode is set.
0
Gigs: Get Your Project Delivered by an Expert

Select from freelancers specializing in everything from database administration to programming, who have proven themselves as experts in their field. Hire the best, collaborate easily, pay securely and get projects done right.

 
LVL 23

Expert Comment

by:Ioannis Paraskevopoulos
ID: 39654127
I think you could store the exit code of the DOS app, and just 'return' it from your main sub.
0
 

Author Comment

by:alconlabs
ID: 39661333
WaitForExit didn't return, and the event handler for the Exited event didn't fire. Turns out I need to set EnableRaisingEvents to get these to work (though OutputDataReceived and ErrorDataReceived events work just fine without it). I'll give the points to TheLearnedOne since he got me headed down the right path.
0
 
LVL 96

Expert Comment

by:Bob Learned
ID: 39661340
Aah, yes, the needle-in-the-haystack...glad you found it.
0

Featured Post

Live: Real-Time Solutions, Start Here

Receive instant 1:1 support from technology experts, using our real-time conversation and whiteboard interface. Your first 5 minutes are always free.

Question has a verified solution.

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

Article by: Ivo
C# And Nullable Types Since 2.0 C# has Nullable(T) Generic Structure. The idea behind is to allow value type objects to have null values just like reference types have. This concerns scenarios where not all data sources have values (like a databa…
Summary: Persistence is the capability of an application to store the state of objects and recover it when necessary. This article compares the two common types of serialization in aspects of data access, readability, and runtime cost. A ready-to…
This Micro Tutorial will give you a basic overview how to record your screen with Microsoft Expression Encoder. This program is still free and open for the public to download. This will be demonstrated using Microsoft Expression Encoder 4.
In this video I am going to show you how to back up and restore Office 365 mailboxes using CodeTwo Backup for Office 365. Learn more about the tool used in this video here: http://www.codetwo.com/backup-for-office-365/ (http://www.codetwo.com/ba…

813 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

18 Experts available now in Live!

Get 1:1 Help Now