pkg_add: Warning: package `digest-20111104' was built for a platform:
pkg_add: NetBSD/i386 5.99.60 (pkg) vs. NetBSD/i386 6.0_BETA (this host)
gmake-3.82nb3: registering info file /usr/pkg/info/make.info
esound-0.2.41nb1: copying /usr/pkg/share/examples/esound/esd.conf to /usr/pkg/etc/esd.conf
===========================================================================
$NetBSD: MESSAGE.common,v 1.3 2008/12/18 16:36:11 jmcneill Exp $

This libao package provides its core library but no output plugins
by itself.  You will have to install an audio/libao-* plugin package
in order to get audio working.

  libao-arts    --  aRts plugin
  libao-esound  --  EsounD (ESD or Enlighten Sound Daemon) plugin
  libao-macosx  --  MacOS X plugin
  libao-oss     --  OSS (Open Sound System) plugin
  libao-pulse   --  PulseAudio plugin
  libao-sun     --  Sun audio plugin

Not all are available on every platform.

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