Re: shellexecuteex in windows service, to run the app persistently

From:
=?Utf-8?B?Z2FuZXNo?= <ganesh@discussions.microsoft.com>
Newsgroups:
microsoft.public.vc.language
Date:
Fri, 21 Jul 2006 16:05:01 -0700
Message-ID:
<0C8E5E8C-069B-4AA4-97B2-B8509C269469@microsoft.com>

I'm not sure what you mean by preventing the service from stopping when the
application closes - as long as you stay in some sort of loop, it will not
end.

Basically i'm using this shellexecuteex within servicestart(). my idea is
when the application is closed by the user it would read 'goto restart' and
restart the application again but instead it just stops the service itself
VOID ServiceStart (DWORD dwArgc, LPTSTR *lpszArgv)
{
restart:
      ShellExecuteEx(&ShExecInfo);
      WaitForSingleObject(ShExecInfo.hProcess,INFINITE);
      goto restart
}

"JJ" wrote:

No, ShellExecuteEx returns a BOOL that is TRUE if successful or FALSE if
not.

If it is TRUE (1), then it started the process.

If it is FALSE (0), an error occurred and you have to call GetLastError() to
find out what the error code is.

The service knows when the application started with ShellExecuteEx closes
because you have the WaitForSingleObject(x,INFINITE) call. That call will
"block" (wait) forever until the process handle you passed to it has ended.
Then it returns. When a process ends, it's handle becomes "signaled" and
that trips WaitForSingleObject.

I'm not sure what you mean by preventing the service from stopping when the
application closes - as long as you stay in some sort of loop, it will not
end.

"ganesh" <ganesh@discussions.microsoft.com> wrote in message
news:7D124071-54E7-4C71-8FE8-D7B2803ED9D8@microsoft.com...

I believe it returns hProcess though i'm not able to capture it.
I removed the ResumeThread now.
One thing I couldn't figure out how does the service know the application
is
closed; and how do i prevent the service from stopping when the
application
is closed

"JJ" wrote:

ResumeThread won't work - that only resumes a thread that was previously
suspended with SuspendThread. A process that has ended is not
suspended -
it has ended.

Are you doing any error checking?

The second time through, what does ShellExecuteEx return?

"ganesh" <ganesh@discussions.microsoft.com> wrote in message
news:D4E809A2-C072-4BE0-B688-2AF8D5E00933@microsoft.com...

ResumeThread(ShExecInfo.hProcess); seems to work; however, the service
stops
once the app has been terminated

restart:
ShExecInfo.cbSize = sizeof(SHELLEXECUTEINFO);
ShExecInfo.fMask = SEE_MASK_NOCLOSEPROCESS;
ShExecInfo.hwnd = NULL;
ShExecInfo.lpVerb = NULL;
ShExecInfo.lpFile = szPath;
ShExecInfo.lpParameters = ""; //"service";
ShExecInfo.lpDirectory = NULL;
ShExecInfo.nShow = SW_SHOW;
ShExecInfo.hInstApp = NULL;
ShellExecuteEx(&ShExecInfo);
WaitForSingleObject(ShExecInfo.hProcess,INFINITE);
ResumeThread(ShExecInfo.hProcess);
//CloseHandle(ShExecInfo.hProcess);
goto restart;

"ganesh" wrote:

I created a service which uses shellexecuteex and WaitForSingleObject
to
open
an application. my requirement is to keep the app running until the
service
is stopped, even if the user terminates the app from task manager.
here
is my
code but it doesn't restart the app when it is closed. any help is
appreciated, thanks

restart:
ShExecInfo.cbSize = sizeof(SHELLEXECUTEINFO);
ShExecInfo.fMask = SEE_MASK_NOCLOSEPROCESS;
ShExecInfo.hwnd = NULL;
ShExecInfo.lpVerb = NULL;
ShExecInfo.lpFile = szPath;
ShExecInfo.lpParameters = ""; //"service";
ShExecInfo.lpDirectory = NULL;
ShExecInfo.nShow = SW_SHOW;
ShExecInfo.hInstApp = NULL;
ShellExecuteEx(&ShExecInfo);
WaitForSingleObject(ShExecInfo.hProcess,INFINITE);
CloseHandle(ShExecInfo.hProcess);
goto restart;

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