Problem trying to start a runnable jar from a C++ application - c++

Question

I need to develop a .exe file that will launch a runnable .jar file which is stored on a subfolder called core. I built the C++ .exe application with sublime text and mingw and it's working fine but there is a small problem that I need to solve. When you execute the .exe file, during a minimum portion of time you can see a black window on screen which is disappearing in some milliseconds and after it the Java .jar application opens. This only happens if I use this .exe. If I double click in the runnable jar the black window doesn't appear.
How can I avoid that black window which dissapears in some milliseconds?
This is the code:
#include <windows.h>
int main()
{
ShellExecute(0, "open", "core.jar", NULL, "core", SW_SHOW);
return 0;
}
I tried also with this code and same result:
ShellExecute(0, "open", "cmd.exe", "/C .\\core\\core.jar", 0, SW_HIDE);
I'm aware there are other similar questions but none of them works for this problem and none of them seems to be applicable to Sublime and gcc.

Answer 1

The problem isn't your call to ShellExecute. Your code is for a console application. Console applications, as one might guess, run in a console (that black window; same as you'd get if you ran cmd.exe).
You can just replace main with WinMain, and simply call ShellExecute in there to launch the jar, and there should be no resulting console window (assuming the jar itself isn't creating one).
See 14 B for how to make a 'windows' app with MingW.

Answer 2

Use CreateProcess() or ShellExecuteEx() which will return you handle to the created process, and with that handle you can kill the process.
Here is an example showing how this works including error handeling.
#include <windows.h>
#include <string>
#include <iostream>
void DisplayError(LPCTSTR errorDesc, DWORD errorCode)
{
TCHAR errorMessage[1024] = TEXT("");
DWORD flags = FORMAT_MESSAGE_FROM_SYSTEM
| FORMAT_MESSAGE_IGNORE_INSERTS
| FORMAT_MESSAGE_MAX_WIDTH_MASK;
FormatMessage(flags,
NULL,
errorCode,
MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
errorMessage,
sizeof(errorMessage) / sizeof(TCHAR),
NULL);
std::cerr << "Error : " << errorDesc << "\n";
std::cerr << "Code = " << errorCode << "\n";
std::cerr << "Message = " << errorMessage << "\n";
}
int main()
{
STARTUPINFO info = { sizeof(info) };
PROCESS_INFORMATION processInfo;
ZeroMemory(&info, sizeof(info));
info.cb = sizeof(info);
ZeroMemory(&processInfo, sizeof(processInfo));
std::string path = "D:\\Java\\jdk1.6.0_26\\bin\\java.exe";
std::string cmdArgs = "java.exe -jar D:\\temp\\sample.jar";
// Start the child process.
if (CreateProcess(path.c_str(), const_cast<char *>(cmdArgs.c_str()), NULL, NULL, TRUE, 0, NULL, NULL, &info, &processInfo))
{
// Wait until child process exits.
WaitForSingleObject(processInfo.hProcess, INFINITE);
// Close process and thread handles.
CloseHandle(processInfo.hProcess);
CloseHandle(processInfo.hThread);
}
else
{
DWORD errorCode = GetLastError();
DisplayError(TEXT("Unable to execute."), errorCode);
}
//system("pause");
}

Answer 3

Finally I discovered that is enough with adding -mwindows to the gcc compile command:
gcc -o launcher launcher.cpp -mwindows