Free ports

find_free_port.rb

# aliases

# alias scripts="cd /Users/tatic/Dropbox/my_projects/myscripts; ls -la"

# alias freeports="scripts;ports >> ports.txt;ruby freeports.rb;rm ports.txt"
# by: TatiCarvalho 2012

# In the command-line: freeports

# v1.1
# example:
# all_ports = ["3000", "3001"]
# busy_ports =  ["3000", "3010"]
# free_port: ["3000", "3001"] - ["3000", "3010"]

busy_ports = []

f = File.open("ports.txt")

f.each do |line|
  busy_ports << /TCP *....../.match(line).to_s.gsub("TCP *:", "")
end

all_ports = ["3000", "3001", "3002", "3003", "3004", "3005", "3006", "3007", "3008", "3009", "3010"]

free_port = (all_ports - busy_ports).first

puts "Free port: #{free_port}"