+# APIs we want
+want_alsa=yes
+want_oss=yes
+want_coreaudio=yes
+
+# Checks for programs.
+AC_PROG_CC
+AC_SET_MAKE
+if test "x$GCC" = xyes; then
+ gcc_werror=-Werror
+else
+ gcc_werror=""
+fi
+
+AC_ARG_WITH([alsa],
+ [AS_HELP_STRING([--without-alsa],
+ [do not build with ALSA support])],
+ [want_alsa=$withval])
+AC_ARG_WITH([oss],
+ [AS_HELP_STRING([--without-oss],
+ [do not build with OSS support])],
+ [want_oss=$withval])
+AC_ARG_WITH([coreaudio],
+ [AS_HELP_STRING([--without-coreaudio],
+ [do not build with Core Audio support])],
+ [want_coreaudio=$withval])
+
+AC_MSG_CHECKING([for a known target platform])