Databases
StackOverflow2013
Postsdbo
POAttachConsole(-1), but Console.WriteLine won't output to parent command prompt?
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POAttachConsole(-1), but Console.WriteLine won't output to parent command prompt?
    primarykey
    data
    text
    <p>If I have set my program to be a <code>Windows Application</code>, and used the <code>AttachConsole(-1)</code> API, how do I get <code>Console.WriteLine</code> to write to the console I launched the application from? It isn't working for me.</p> <p>In case it is relevant, I'm using Windows 7 x64, and I have UAC enabled. Elevating doesn't seem to solve the problem though, nor does using <code>start /wait</code>.</p> <p><strong>Update</strong></p> <p>Some additional background that might help:</p> <p>I've just discovered that if I go to the command prompt and type <code>cmd /c MyProgram.exe</code>, <strong>Then console output works</strong>. The same is true if I launch a command prompt, open a <code>cmd.exe</code> sub-process, and run the program from that sub-shell.</p> <p>I've also tried logging out and back in, running from a cmd.exe launched from the start menu (as opposed to right-click -> command prompt), and running from <a href="http://sourceforge.net/projects/console/" rel="nofollow noreferrer">a console2 instance</a>. None of those work.</p> <p><strong>Background</strong></p> <p>I've read on other sites and in several SO answers that I can call the win32 API <code>AttachConsole</code> to bind my Windows Application to the console that ran my program, so I can have something that is "both a console application, and a Windows application".</p> <p>For example, this question: <a href="https://stackoverflow.com/questions/6546455/is-it-possible-to-log-message-to-cmd-exe-in-c-net">Is it possible to log message to cmd.exe in C#/.Net?</a>.</p> <p>I've written a bunch of logic to make this work (using several other APIs), and I have gotten every other scenario to work (including redirection, which others have claimed won't work). The only scenario left is to get <code>Console.WriteLine</code> to write to the console I launched my program with. From everything I've read this is supposed to work if I use <code>AttachConsole</code>.</p> <p><strong>Repro</strong></p> <p>Here's a minimal sample - Note that the project is set to be a <code>Windows Application</code>:</p> <pre><code>using System; using System.ComponentModel; using System.Runtime.InteropServices; using System.Windows.Forms; class Program { [STAThread] static void Main(string[] args) { if (!AttachConsole(-1)) { MessageBox.Show( new Win32Exception(Marshal.GetLastWin32Error()) .ToString() ); } Console.WriteLine("Test"); } [DllImport("kernel32.dll", SetLastError = true, ExactSpelling = true)] private static extern bool AttachConsole(int processId); } </code></pre> <ul> <li>When I run this from a command prompt, I don't get an error, but I don't get any console output either. <em>This is the problem</em></li> <li>If I add extra message boxes anywhere in the execution flow of the app, the message box gets displayed. I expect this, so all good here.</li> <li>When I run this from Visual Studio or by double clicking on it, a message box with an error is displayed. I expect this, so no worries here (will use <code>AllocConsole</code> in my real app).</li> </ul> <p>If I call <code>Marshal.GetLastWin32Error</code> after the call to <code>Console.WriteLine</code>, I get the error "System.ComponentModel.Win32Exception (0x80004005): The handle is invalid". I suspect that attaching to the console is causing <code>Console.Out</code> to get messed up, but I'm not sure how to fix it.</p>
    singulars
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PTQuestion
    1. USCommunity
    1. USMerlyn Morgan-Graham
    plurals
    1. PL
      singulars
      1. LTLinked
    2. PL
      singulars
      1. LTLinked
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    3. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POAttachConsole(-1), but Console.WriteLine won't output to parent command prompt?
      1. USMr47
      1. VTFavorite
    2. VO
      singulars
      1. POAttachConsole(-1), but Console.WriteLine won't output to parent command prompt?
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
      singulars
      1. POAttachConsole(-1), but Console.WriteLine won't output to parent command prompt?
      1. This table or related slice is empty.
      1. VTUpMod
    1. COWhy don't you mark your program as console application?
      singulars
      1. POAttachConsole(-1), but Console.WriteLine won't output to parent command prompt?
      1. USCodesInChaos
    2. COVery strange ... I also use `AttachConsole(-1)` in an application and it works without issue. I will compare the code when I get into work and post-back if there is any difference. @CodeInChoas: If you create it as a Console Application, you will always have the console window in the background. By using AttachConsole you get the best of both - an application that when opened via the command line (console) it will write to the console streams.
      singulars
      1. POAttachConsole(-1), but Console.WriteLine won't output to parent command prompt?
      1. USDennis
    3. CO@CodeInChaos: That seems like the "well, duh!" solution :) But I don't really want "both a console and Windows app", I want *either* a console or Windows app, based on command line switches. And I don't want the console to blink off the screen when I launch it. This is a pretty common scenario, and I've found about a dozen threads to get everything working, including this piece. Except that this piece isn't working. If you think I should make my requirements more clear in my question, let me know and I'll gladly fix it.
      singulars
      1. POAttachConsole(-1), but Console.WriteLine won't output to parent command prompt?
      1. USMerlyn Morgan-Graham
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload