$ ruby LPCParser.rb --rule=translation_unit < foobar.c 
waiting for incoming connection on port 49100
Accepted connection from 127.0.0.1:28694
/usr/home/pope/.rvm/gems/ruby-1.9.2-p136/gems/antlr3-1.8.5/lib/antlr3/debug/socket.rb:51:in `handshake': uninitialized constant Socket::SOL_TCP (NameError)
        from /usr/home/pope/.rvm/gems/ruby-1.9.2-p136/gems/antlr3-1.8.5/lib/antlr3/debug.rb:160:in `initialize'
        from /usr/home/pope/.rvm/gems/ruby-1.9.2-p136/gems/antlr3-1.8.5/lib/antlr3/modes/ast-builder.rb:21:in `initialize'
        from LPCParser.rb:183:in `initialize'
        from /usr/home/pope/.rvm/gems/ruby-1.9.2-p136/gems/antlr3-1.8.5/lib/antlr3/main.rb:458:in `new'
        from /usr/home/pope/.rvm/gems/ruby-1.9.2-p136/gems/antlr3-1.8.5/lib/antlr3/main.rb:458:in `recognize'
        from /usr/home/pope/.rvm/gems/ruby-1.9.2-p136/gems/antlr3-1.8.5/lib/antlr3/main.rb:162:in `execute'
        from /usr/home/pope/.rvm/gems/ruby-1.9.2-p136/gems/antlr3-1.8.5/lib/antlr3/recognizers.rb:1260:in `main'
        from LPCParser.rb:22488:in `block in <module:LPC>'
