gcap.rb - Screen capture

gcap.rb

#!/usr/bin/env ruby

# $ grep GCAP_SAVE_DIR ~/.bash_profile
# export GCAP_SAVE_DIR=/Users/YOUR/SAVE/DIR

dir = ENV['GCAP_SAVE_DIR']

n = 0
while
  filename = "#{dir}/#{n}.png"
  break if not File.exist?(filename) 
  n += 1
end

# $ man screencapture
system(%Q(screencapture -i #{filename}))

# Add transparent 1 pixel to the png image.
system("transpoint #{filename}")