require 'nmap/command'

Nmap::Command.run do |nmap|
  nmap.connect_scan   = true
  nmap.service_scan   = true
  nmap.output_xml     = 'scan.xml'
  nmap.verbose        = true

  nmap.ports   = [20, 21, 22, 23, 25, 80, 110, 443, 512, 522, 8080, 1080]
  nmap.targets = '192.168.1.*'
end

require 'nmap/command'

Nmap::Command.sudo do |nmap|
  nmap.syn_scan       = true
  nmap.os_fingerprint = true
  nmap.service_scan   = true
  nmap.output_xml     = 'scan.xml'
  nmap.verbose        = true

  nmap.ports   = [20, 21, 22, 23, 25, 80, 110, 443, 512, 522, 8080, 1080]
  nmap.targets = '192.168.1.*'
end

require 'nmap/xml'

Nmap::XML.open('scan.xml') do |xml|
  xml.each_host do |host|
    puts "[#{host.ip}]"

    host.each_port do |port|
      puts "  #{port.number}/#{port.protocol}\t#{port.state}\t#{port.service}"
    end
  end
end

require 'nmap/xml'

Nmap::XML.open('nse.xml') do |xml|
  xml.each_host do |host|
    puts "[#{host.ip}]"

    host.scripts.each do |name,output|
      output.each_line { |line| puts "  #{line}" }
    end

    host.each_port do |port|
      puts "  [#{port.number}/#{port.protocol}]"

      port.scripts.each do |id,script|
        puts "    [#{id}]"

        script.output.each_line { |line| puts "      #{line}" }
      end
    end
  end
end

$ sudo apt install nmap

$ sudo dnf install nmap

$ brew install nmap

$ gem install ruby-nmap