I just did a quick check, and I'm not seeing anywhere in the ruby
source where it sets an envvar named _. Perhaps this envvar is a
feature of bash or linux or something other than ruby.
···
On 7/28/10, Roger Pack <rogerpack2005@gmail.com> wrote:
I haven't checked yet whether there's a bug filed against JRuby for
the lack of support for ENV['_'], which obviously wins the minimalist
contest 
ENV['_']
doesn't seem to work for me on windows at all:
ENV['_']
=> nil
Thought it might still be a bug in jruby that it not have one under
linux, I'm not entirely sure.
Caleb Clausen wrote:
I haven't checked yet whether there's a bug filed against JRuby
for the lack of support for ENV['_'], which obviously wins the
minimalist contest
ENV['_'] doesn't seem to work for me on windows at all:
ENV['_']
=> nil
Thought it might still be a bug in jruby that it not have one under
linux, I'm not entirely sure.
I just did a quick check, and I'm not seeing anywhere in the ruby source where it sets an envvar named _. Perhaps this envvar is a feature of bash or linux or something other than ruby.
Yeah, I think it's just a shell feature:
$ ruby -e 'p ENV["_"]'
"/usr/local/bin/ruby"
$ env ruby -e 'p ENV["_"]'
"/usr/bin/env"
That's the behavior in both zsh and bash.
Found this in some bash docs:
···
On 7/28/10, Roger Pack <rogerpack2005@gmail.com> wrote:
The underscore variable is set at shell startup and contains the
absolute file name of the shell or script being executed as passed in
the argument list. Subsequently, it expands to the last argument to
the previous command, after expansion. It is also set to the full
pathname of each command executed and placed in the environment
exported to that command. When checking mail, this parameter holds
the name of the mail file.
Ah, good detectorizing and that explains the JRuby "issue" -- even
though $JRUBY_HOME/bin/jruby is a bash script, it contains this line:
JRUBY_SHELL=/bin/sh
so apparently no '_' environment variable will be forthcoming.
Ya learn something every day!
···
On Wed, Jul 28, 2010 at 3:14 PM, Joel VanderWerf <joelvanderwerf@gmail.com> wrote:
That's the behavior in both zsh and bash.
--
Hassan Schroeder ------------------------ hassan.schroeder@gmail.com
twitter: @hassan