I am trying to launch a URL from LUA and using emSpawn:
 
os.execute("emSpawn.exe /! http://msn.com")  
 
Why do I need to close the DOS window before the Browser launches the page? I just want the page to open in the Browser...

With DOS window, I meant the Command window (cmd.exe).
 
Best explained with examples:
 
1.
os.execute("notepad.exe")  
=> Opens a cmd window and Notepad. However, LUA is halted until notepad closed
 
2.
os.execute("emSpawn.exe / notepad.exe")  
=> Doesn't work . I only get 2 cmd windows that opens/closes
 
3.
os.execute("emSpawn.exe /! notepad.exe")  
=> Almost works as expected. Opens and closes a cmd window (unexpected), and then opens Notepad
 
 
 
Now, I would like to open a URL instead of Notepad.
 
4.
os.execute("emSpawn.exe /! http://msn.com")  
=> Cmd window opens and execution halted. I need to close the window before the Browser URL is launched and execution continues
 
How would I open the Browser URL w/o having to close the cmd window?
 
Notes:
 
1. Not sure how to open a URL from cmd promt? Simply typing the URL doesn't work (actually surprised that  example 4 works at all)
 
2. However, I can open a URL from Windows Start|Run by simply typing the URL
 
3. 1. I don't understand what you mean by  
does a "exit && emSpawn.exe ....etc..." do any better ?  

Quote from rb on 05/29/09 at 22:10:29:

 
Have you tried "start /b"?
From WinXP Help "Command-line reference A-Z"
Quote: