How to start console app minimized or with no console?

I have a Windows GUI program in which I spawn another process that runs in a DOS shell (using the _spawnl ) command.

I was wondering how to get this process to either start with the console minimized, And/OR:

with the console not appearing at all? It really doesn't need to be seen, only for debugging messages that are sometimes printed out.

Thanks,

Tom
gunnAsked:
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

galkinCommented:
Use CreateProcess instead. wShowWindow member of STARTUPINFO structure passed to CreateProcess contaons information of main process window. Set it to SW_HIDE or SW_SHOWMINIMIZED. Be sure to specify STARTF_USESHOWWINDOW in dwFlags filed of STARTUPINFO
0
gunnAuthor Commented:
I've tried to use this for awhile now and I can't get it to work, no matter what. Heres the sample code I wrote to use the CreateProcess function. What am I doing wrong? Grrrrrr

Its hanging up on CreateProcess for a couple of seconds, and then it gives me a "First-chance exception in TestSpawn.exe (KERNEL32.DLL) 0xC000005 : Access Violation"  errors.

I've also had it hang up on the
lpInfoToPass->cb              = 68;  
because sometimes lpInfoToPass address is 0x00000 at this point? But then sometimes its ok too.....

/*---------------------*/

#include <windows.h>

#include <process.h>

#include <string.h>

#include <stdio.h>

#include <stdlib.h>



void main()

{

      char err_string[256] = "Error in Spawning: ";

      BOOL status1;

      extern int errno;

    /* A small console app to execute */

      char *child_full_name = "D:\\DTM_Test\\DTM_ReadTest.exe";



      LPPROCESS_INFORMATION lpProcessInfo;  

      LPSTARTUPINFO lpInfoToPass;



      lpInfoToPass->cb              = 68;  /* ???? how to get? */

      lpInfoToPass->lpReserved  = NULL;

      lpInfoToPass->lpDesktop        = NULL;

      lpInfoToPass->lpTitle        = NULL;

      lpInfoToPass->dwFlags        = STARTF_USESHOWWINDOW;

      lpInfoToPass->cbReserved2 = 0;

      lpInfoToPass->lpReserved2 =  NULL;

      lpInfoToPass->wShowWindow = SW_SHOWMINIMIZED;



      printf("Testing Spawning Process\n");



/*

      status1 = _spawnl( _P_NOWAIT, child_full_name,

                                 child_full_name, NULL );

*/

 

  status1 = CreateProcess( child_full_name, child_full_name, NULL, NULL, FALSE,

                      CREATE_NEW_CONSOLE, 0, 0,

                     lpInfoToPass, lpProcessInfo );





      /* print out the error message if status = -1 */

      if( errno != 0 )

        perror( err_string );



      exit(0);

}
0
mikeblasCommented:
You're incorrectly initializing nearly everything, and you don't know the difference between allocated memory and a pointer to allocated memory.

Here's some code that should be a lot closer to working than what you have written:

char *child_full_name = "D:\\DTM_Test\\DTM_ReadTest.exe";

// these are structures, not pointers

PROCESS_INFORMATION ProcessInfo;
STARTUPINFO InfoToPass;

/* lpInfoToPass->cb = 68;
      ???? how to get? */
// use sizeof()!

InfoToPass.cb = sizeof(InfoToPass);
InfoToPass.lpReserved = NULL;
InfoToPass.lpDesktop = NULL;
InfoToPass.lpTitle = NULL;
InfoToPass.dwFlags = STARTF_USESHOWWINDOW;
InfoToPass.cbReserved2 = 0;
InfoToPass.lpReserved2 = NULL;
InfoToPass.wShowWindow = SW_SHOWMINIMIZED;

printf("Testing Spawning Process\n");

// use ampersand on structures to get a pointer to
// the structures you intialized above

BOOL status1;
status1 = CreateProcess(child_full_name, "", NULL, NULL, FALSE,
   CREATE_NEW_CONSOLE, NULL, NULL, &InfoToPass, &ProcessInfo);

// errno is set by c runtime routnes, but CreateProcess() is a
// windows API. check the return code and GetLastError() instead
// of errno

if (status1)
{
   printf("it worked");
}
else
{
   printf("it failed.  Error code == %d", GetLastError());
}

.B ekiM




0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Microsoft Development

From novice to tech pro — start learning today.