Run windows .exe and wait for completion

[Al Hart]

For the RpTreeMaker app I want to run a Windows .exe, passing it an argument, and wait for the execution to complete.

We have been using system(command_line) for this, but as SketchUp waits, it uses up too many machine cycles.

I tried Win32API and ShellExecute, but it doesn't wait.

I tried UI.openURL(sexec), but couldn't see to get it to work with arguments.

Does anyone have any other ideas?

[Petruscaleus]

Well, I doubt this will be any help to you, but in simple batch file I would use the START command along with the parameter /WAIT

start /wait yourprogram.exe <parameters you want to pass along>
next_command (will be executed when yourprogram.exe has terminated)

...but perhaps you can use it somehow.

[Al Hart]

I was finally able to do this using Win32API and a function I call "call_and_wait".

def self;;call_and_wait(scommand_line)
		cp_params = 'LPLLLLLLPP'
		create_process = Win32API.new('kernel32','CreateProcess', cp_params, 'I')
		startinfo = [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0].pack('LLLLLLLLLLLLSSLLLL')

		# place holder for results
		procinfo  = [0,0,0,0].pack('LLLL')

		trace("scommand_line; %s", scommand_line)
		cp = create_process.call(0, scommand_line, 0, 0, 0, 0, 0, 0, startinfo, procinfo)
		trace("create_process returned; %s", cp)
		if (cp == 0)
			return
		end#if 
			
		# get process if of process we created
		hProcess = procinfo.unpack("LLLL")[0]	
		trace("hProcess; %s waiting...", hProcess)
		if (hProcess == 0)
			return
		end#if 
	
		waitForSingleObject = Win32API.new("kernel32","WaitForSingleObject",['L','L'],'L')
		a = waitForSingleObject.Call( hProcess, 0xFFFFFFFF ) # wait forever
		trace("waitForSingleObject returned; %s", a)
	end#def

The WaitForSingleObject waits for the task to complete without using up resources.

The ruby command system(command_line) runs the commands and waits for it, but uses up 1/2 of the resources of the machine in a tight loop checking to see if the command is done yet.