From: Jan Svitok <jan.svitok@...>
Date: 2006-08-11T17:07:27+09:00
Subject: Re: Start an external application - How?

On 8/11/06, ilsemanetor@gmail.com <ilsemanetor@gmail.com> wrote:
>
> Joe Percival wrote:
> > I don't need details, just a push in the right direction.
> >
> > How do you start a series of external applications from within ruby (on
> > windows).  For example, I want to start mywebcamapp.exe and
> > myweatherapp.exe.
> >
> > Also, is it possible to have a ruby script that will stop an external
> > process?
> >
> > Thanks,
> > joe
> >
> > --
> > Posted via http://www.ruby-forum.com/.
>
> Anyone more knowledgable, please correct the below:
> Basically, you will either want to use Threads or multiple processes.I
> don't have much experience with threads, and little more with
> processes. From the pickaxe (Programming Ruby), it seems that threads
> may wait for the operating system call to finish before allowing both
> itself and all other threads to continue. A thread is also internal to
> the currently running ruby or irb session, and as such are much more
> useful executing ruby code. That being said, Threads provide alot of
> neat features and such.
>
> What you probably want is a new process.
>
> fork do
>   `my_program.exe`
> end
>
> and then if you ever want you program to wait for the termination of
> all your applications running, use:
>
> Process.waitall
>
> Note that forking and new processes and such are many times operating
> system dependent. I have no clue as to if Windows supports this (I

On Windows, fork in not implemented. :(
For this purpose I mainly use `start "" progname.exe` (note the double quotes:
if the first parameter has quotes, it's the title of the window. That
means `start "c:\Program Files\Anything.exe" won't start the
program...) start will start program and return, so ruby can
continue...

Jano