Ruby: How to determine if file being read is binary or text

Question

Hi,

I am writing a program in Ruby which will search for strings in text files within a directory - similar to Grep.

I don't want it to attempt to search in binary files but I can't find a way in Ruby to determine whether a file is binary or text.

The program needs to work on both Windows and Linux.

If anyone could point me in the right direction that would be great.

Thanks,

Xanthalas

Answer 1

gem install ptools
require 'ptools'
File.binary?(file)

Answer 2

libmagic is a library which detects filetypes. For this solution I assume, that all mimetype's which start with text/ represent text files. Eveything else is a binary file. This assumption is not correct for all mime types (eg. application/x-latex, application/json), but libmagic detect's these as text/plain.

require "filemagic"

def binary?(filename)
  begin
    fm= FileMagic.new(FileMagic::MAGIC_MIME)
    !(fm.file(filename)=~ /^text\//)
  ensure
    fm.close
  end
end