From: Joel VanderWerf <vjoel@...>
Date: 2004-01-06T07:20:08+09:00
Subject: Re: name of current ruby iterpreter

Ryan Pavlik wrote:
> On Tue, 6 Jan 2004 06:09:47 +0900
> Joel VanderWerf <vjoel@PATH.Berkeley.EDU> wrote:
> 
> 
>>How can I find the name of the current ruby interpreter? It's not $0, 
>>since that's the main ruby script. I want to be able to start another 
>>process using the same interpreter, whatever that happens to be.
>>
> 
> 
>     require 'rbconfig'
>     
>     ruby = Config::CONFIG.fetch('bindir') + "/" +
>            Config::CONFIG.fetch('RUBY_INSTALL_NAME')
>     ruby = Config.expand(ruby)
>     
>     exec ruby, "-e", 'puts VERSION'

Almost there. It won't work if you've got 1.8.0 and 1.8.1 both installed 
(if you installed 1.8.1 later, requiring 'rbconfig' generates an error). 
And it doesn't detect that you started ruby with an alias ('alias 
rv=ruby -v)', but it's good enough for my purposes. What I was looking 
for was a way to see the original command line. On linux I could use the 
proc file system, but that's just linux...

Thanks!

> AFAIK, "/" works in win32.  HTH,

It does, though I tend to use File.join for clarity.