sha1sum.rb

# Usage:
#   ruby sha1sum.rb FILE
#
# Compare results with http://en.wikipedia.org/wiki/Sha1sum
# http://lists.gnupg.org/pipermail/gnupg-announce/2004q4/000184.html (Windows)

require 'digest/sha1'

hashfunc = Digest::SHA1.new
open(ARGV[0], "rb") do |io|
  while(!io.eof)
    hashfunc.update(io.readpartial(1024))
  end
end
puts hashfunc.hexdigest