From: Robert Klemme <bob.news@...>
Date: 2004-08-30T20:25:27+09:00
Subject: Re: File read progress


"Tim Hunter" <cyclists@nc.rr.com> schrieb im Newsbeitrag
news:PXqYc.548$MO3.87112@twister.southeast.rr.com...
> JG wrote:
>
> > 2) query the filehandle to tell me where I am at with respect to the
total
> > file size.
>
> See the pos method in IO.

#pos will only help if you know the number of lines beforehand.  That's
typically not the case.  How about this:

def read_records(file, rx, report = $stderr)
  size = File.size file

  File.open( file ) do |io|
    rec = []
    sum = 0
    threshold = 10

    while ( line = io.gets )
      sum += line.size
      line.chomp!

      perc = sum * 100.0 / size

      if perc > threshold
        report.printf "Read %.1f%\n", perc
        threshold += 10
      end

      rec << line if rx =~ line
    end

    return rec
  end
end

Then you can do

records = read_records("foo.bar", /keyword/)
# eat the status info:
records = read_records("foo.bar", /keyword/, StringIO.new)

Kind regards

    robert