~ian # gem install airstream                                                                                root@iris
Building native extensions.  This could take a while...
ERROR:  Error installing airstream:
	ERROR: Failed to build gem native extension.

    /usr/local/bin/ruby19 extconf.rb
checking for dns_sd.h... no
unable to find dnssd header
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of
necessary libraries and/or headers.  Check the mkmf.log file for more
details.  You may need configuration options.

Provided configuration options:
	--with-opt-dir
	--without-opt-dir
	--with-opt-include
	--without-opt-include=${opt-dir}/include
	--with-opt-lib
	--without-opt-lib=${opt-dir}/lib
	--with-make-prog
	--without-make-prog
	--srcdir=.
	--curdir
	--ruby=/usr/local/bin/ruby19
	--with-warnings
	--without-warnings
	--with-dnssd-dir
	--without-dnssd-dir
	--with-dnssd-include
	--without-dnssd-include=${dnssd-dir}/include
	--with-dnssd-lib
	--without-dnssd-lib=${dnssd-dir}/lib


Gem files will remain installed in /usr/local/lib/ruby/gems/1.9/gems/dnssd-2.0 for inspection.
Results logged to /usr/local/lib/ruby/gems/1.9/gems/dnssd-2.0/ext/dnssd/gem_make.out
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