How to connect to a rfcomm/l2cap server in Ruby

bluetooth_socket_example.rb

#/usr/bin/env ruby

require 'socket'

addr    = "00:11:22:33:44:55"
rf_chan = 23
l2_psm  = 15

# rfcomm client
s = Socket.new 31, 1, 3 # (31 = AF_BLUETOOTH, 1 = SOCK_STREAM, 3 = BTPROTO_RCOMM)
sockaddr = [31, 0, *addr.split(':').reverse_each.map(&:hex), rf_chan, 0].pack('C*')
s.connect sockaddr
# perform operations
s.close

#l2cap client
s = Socket.new 31, 5, 0 # (31 = AF_BLUETOOTH, 5 = SOCK_SEQPACKET, 0 = BTPROTO_L2CAP)
sockaddr = [31, 0, l2_psm, 0, *addr.split(':').reverse_each.map(&:hex), 0, 0, 0, 0].pack('C*')
s.connect sockaddr
# perform operations
s.close