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copied!<p>The problem is that if you redirect <code>StandardOutput</code> and/or <code>StandardError</code> the internal buffer can become full. Whatever order you use, there can be a problem:</p> <ul> <li>If you wait for the process to exit before reading <code>StandardOutput</code> the process can block trying to write to it, so the process never ends.</li> <li>If you read from <code>StandardOutput</code> using ReadToEnd then <em>your</em> process can block if the process never closes <code>StandardOutput</code> (for example if it never terminates, or if it is blocked writing to <code>StandardError</code>).</li> </ul> <p>The solution is to use asynchronous reads to ensure that the buffer doesn't get full. To avoid any deadlocks and collect up all output from both <code>StandardOutput</code> and <code>StandardError</code> you can do this:</p> <p>EDIT: See answers below for how avoid an <strong>ObjectDisposedException</strong> if the timeout occurs.</p> <pre><code>using (Process process = new Process()) { process.StartInfo.FileName = filename; process.StartInfo.Arguments = arguments; process.StartInfo.UseShellExecute = false; process.StartInfo.RedirectStandardOutput = true; process.StartInfo.RedirectStandardError = true; StringBuilder output = new StringBuilder(); StringBuilder error = new StringBuilder(); using (AutoResetEvent outputWaitHandle = new AutoResetEvent(false)) using (AutoResetEvent errorWaitHandle = new AutoResetEvent(false)) { process.OutputDataReceived += (sender, e) => { if (e.Data == null) { outputWaitHandle.Set(); } else { output.AppendLine(e.Data); } }; process.ErrorDataReceived += (sender, e) => { if (e.Data == null) { errorWaitHandle.Set(); } else { error.AppendLine(e.Data); } }; process.Start(); process.BeginOutputReadLine(); process.BeginErrorReadLine(); if (process.WaitForExit(timeout) && outputWaitHandle.WaitOne(timeout) && errorWaitHandle.WaitOne(timeout)) { // Process completed. Check process.ExitCode here. } else { // Timed out. } } } </code></pre>

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