simple http access log filter, assuming last field is time in microseconds

whittle.rb

#!/usr/bin/env ruby

# assumes apache log file looks like this (all we care about is the final field):
# LogFormat "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-agent}i\" %D" custom

require 'optparse'

options = {}
options[:time] = 1
OptionParser.new do |opts|
  opts.banner = "Usage: whittle.rb [options] logfile"

  opts.on("-t", "--time t", "Time (in seconds) to filter on") do |t|
    options[:time] = t.to_i
  end
end.parse!

begin
  ARGF.each do |line|
    time = line.split(' ').last.to_i
    puts line if time > (options[:time] * 1000000)
  end
rescue Interrupt
  # just die if someone hits ctrl-c
end