From: Nobuyoshi Nakada <nobu@...>
Date: 2007-06-20T03:16:36+09:00
Subject: Re: Check for text file

Hi,

At Wed, 20 Jun 2007 02:10:57 +0900,
Ryan Davis wrote in [ruby-talk:256206]:
> > After some research I still cannot find a way how to see if a file is
> > plain text or binary. In fact I want to check if a file is plain  
> > text no
> > matter what characters are in it.
> 
> http://blog.zenspider.com/archives/2006/08/i_miss_perls_b.html

You can use String#count:

  def File.binary?(path)
    s = read(path, 4096) and
    !s.empty? and
    (/\0/n =~ s or s.count("\t\n -~").to_f/s.size<=0.7)
  end

In any case, it doesn't work for non-ascii files.

-- 
Nobu Nakada