From: james.d.masters@...
Date: 2007-06-17T02:50:08+09:00
Subject: Re: Process id

On Jun 16, 9:13 am, Gianni Dupro <tetta...@lu.unisi.ch> wrote:
> Hi everybody I m nobie of ruby
>
> I need some hint about to catch a id of a certain process
>
> for instance if I run this line of code
>
> `ruby file.rb` there is a possibility to have the id of this process
> (file.rb process)
>
> my problem if the file.rb was lock I need the pId for kill it
>
> Thanks to all
>
> Best Regards
>
> joksy
>
> --
> Posted viahttp://www.ruby-forum.com/.

A quick look at Kernel#` in the Ruby documentation (http://www.ruby-
doc.org/core/) mentions a special (Perl-esque) variable $? which can
be used after calling a system command with ``:

bash-2.05a$ irb.bat
irb(main):001:0> `echo "hi"`
=> "\"hi\"\n"
irb(main):002:0> $?.pid
=> 3124

And as you can see that variable happens to have a #pid method.  Does
anyone know if there is a better way without using the esoteric $?
variable?

-James