From: Sam Stephenson <sstephenson@...>
Date: 2005-11-07T10:11:36+09:00
Subject: Re: Lazy fun: Make unary minus silence stderr for backticks

On 11/6/05, Mauricio Fern�ndez <mfp@acm.org> wrote:
> batsman@tux-chan:/tmp$ cat test.rb
> require 'rbconfig'
> def nostderr
>   old = STDERR.dup
>   # unsure about the next line
>   file = (::Config::CONFIG["arch"] =~ /dos|win32|mingw/) ? "NUL" : "/dev/null"
>   STDERR.reopen(file)
>   STDERR.sync = true  # you want this so `hello3` still outputs something below...
>   yield
> ensure
>   STDERR.reopen(old)
> end
>
> `hello`
> nostderr { `hello2`; $stderr.puts "foo"  }
> `hello3`
> batsman@tux-chan:/tmp$ ruby test.rb
> test.rb:2: command not found: hello
> test.rb:2: command not found: hello3

Interesting, I didn't know that reopening STDERR would affect
subshells. It's more code but I think I prefer this approach.

Sam