Fix dwFlags on CreateProcessW calls

[WoLfulus]

Command prompt is still being shown when calling os.execute on Windows. The previous flags always results in 0 because flags should be merged with an OR operator.

Bugsquad edit: May help with #52242.

[mhilbrunner]

This is the right fix according to the official docs. Will make sure and test.

[mhilbrunner]

Built & tested, seems to work fine. Funnily enough, I don't actually seem to get a console window with current master though? Not sure why.

Anyway, this is correct, the current code doesn't work.

Edit: does the additional console window without this only show up in release exports? May be the case the otherwise existing default console window gets inherited. Will check.

[akien-mga]

Thanks!

[WoLfulus]

Built & tested, seems to work fine. Funnily enough, I don't actually seem to get a console window with current master though? Not sure why.

Anyway, this is correct, the current code doesn't work.

Edit: does the additional console window without this only show up in release exports? May be the case the otherwise existing default console window gets inherited. Will check.

@mhilbrunner It's deeper than that though. This doesn't fix all the problems related to command prompts showing up (for me at least), it fixes only the flag passing that was wrong.

The main problem when trying to launch an executable from godot (I'm building a game launcher) is that OS.execute will always pass a non-null r_pipe value

godot/core/core_bind.cpp

Line 230 in 4d96d37

Error err = ::OS::get_singleton()->execute(p_path, args, &pipe, &exitcode, p_read_stderr);

This makes the process execute with _wpopen

godot/platform/windows/os_windows.cpp

Line 424 in 4d96d37

FILE *f = _wpopen((LPCWSTR)(command.utf16().get_data()), L"r");

instead of CreateProcessW + Win32 pipe functions.

I had to comment this whole block and start using a custom built template to get rid of that command prompt as I'm not interested in the output, only the exit codes.

godot/platform/windows/os_windows.cpp

Lines 416 to 442 in 4d96d37

	if (r_pipe) {
	if (read_stderr) {
	command += " 2>&1"; // Include stderr
	}
	// Add extra quotes around the full command, to prevent it from stripping quotes in the command,
	// because _wpopen calls command as "cmd.exe /c command", instead of executing it directly
	command = _quote_command_line_argument(command);
	FILE *f = _wpopen((LPCWSTR)(command.utf16().get_data()), L"r");
	ERR_FAIL_COND_V_MSG(!f, ERR_CANT_OPEN, "Cannot create pipe from command: " + command);
	char buf[65535];
	while (fgets(buf, 65535, f)) {
	if (p_pipe_mutex) {
	p_pipe_mutex->lock();
	}
	(*r_pipe) += String::utf8(buf);
	if (p_pipe_mutex) {
	p_pipe_mutex->unlock();
	}
	}
	int rv = _pclose(f);
	if (r_exitcode) {
	*r_exitcode = rv;
	}
	return OK;
	}