Service hangs up at WaitForExit after calling batch file

Question

I have a service that sometimes calls a batch file. The batch file takes 5-10 seconds to execute:

System.Diagnostics.Process proc = new System.Diagnostics.Process(); // Declare New Process
    proc.StartInfo.FileName = fileName;
    proc.StartInfo.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden;
    proc.StartInfo.CreateNoWindow = true;
    proc.Start();
    proc.WaitForExit();

The file does exist and the code works when I run the same code in-console. However when it runs inside the service, it hangs up at WaitForExit(). I have to kill the batch file from the Process in order to continue. (I am certain the file exists, as I can see it in the processes list.)

How can I fix this hang-up?

Update #1:

Kevin's code allows me to get output. One of my batch files is still hanging.

"C:\EnterpriseDB\Postgres\8.3\bin\pg_dump.exe" -i -h localhost -p 5432 -U postgres -F p -a -D -v -f "c:\backupcasecocher\backupdateevent2008.sql" -t "\"public\".\"dateevent\"" "DbTest"

The other batch file is:

"C:\EnterpriseDB\Postgres\8.3\bin\vacuumdb.exe" -U postgres -d DbTest

I have checked the path and the postgresql path is fine. The output directory does exist and still works outside the service. Any ideas?

Update #2:

Instead of the path of the batch file, I wrote the "C:\EnterpriseDB\Postgres\8.3\bin\pg_dump.exe" for the proc.StartInfo.FileName and added all parameters to proc.StartInfo.Arguments. The results are unchanged, but I see the pg_dump.exe in the process window. Again this only happens inside the service.

Update #3:

I have run the service with a user in the administrator group, to no avail. I restored null for the service's username and password

Update #4:

I created a simple service to write a trace in the event log and execute a batch file that contains "dir" in it. It will now hang at proc.Start(); - I tried changing the Account from LocalSystem to User and I set the admnistrator user and password, still nothing.

Answer 1

Here is what i use to execute batch files:

proc.StartInfo.FileName                 = target;
proc.StartInfo.RedirectStandardError    = true;
proc.StartInfo.RedirectStandardOutput   = true;
proc.StartInfo.UseShellExecute          = false;

proc.Start();

proc.WaitForExit
    (
        (timeout <= 0)
            ? int.MaxValue : timeout * NO_MILLISECONDS_IN_A_SECOND *
                NO_SECONDS_IN_A_MINUTE
    );

errorMessage = proc.StandardError.ReadToEnd();
proc.WaitForExit();

outputMessage = proc.StandardOutput.ReadToEnd();
proc.WaitForExit();

I don't know if that will do the trick for you, but I don't have the problem of it hanging.

Answer 2

using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Diagnostics;
    namespace VG
    {
        class VGe
        {
            [STAThread]
            static void Main(string[] args)
            {
                Process proc = null;
                try
                {                
                    string targetDir = string.Format(@"D:\adapters\setup");//this is where mybatch.bat lies
                    proc = new Process();
                    proc.StartInfo.WorkingDirectory = targetDir;
                    proc.StartInfo.FileName = "mybatch.bat";
                    proc.StartInfo.Arguments = string.Format("10");//this is argument
                    proc.StartInfo.CreateNoWindow = false;
                    proc.Start();
                    proc.WaitForExit();
                }
                catch (Exception ex)
                {
                    Console.WriteLine("Exception Occurred :{0},{1}", ex.Message,ex.StackTrace.ToString());
                }
            }
        }
    }