+AC_ARG_WITH(with_zlib, [ --with-zlib use zlib compression if present])
+dnl Checks for the zlib compression library.
+if test "x$with_zlib" != xno ; then
+ AC_CHECK_HEADERS(zlib.h,
+ [AC_CHECK_LIB(z, zlibVersion,
+ [ok_zlib=yes],,
+ )])
+fi
+
+if test "x$ok_zlib" = xyes ; then
+ LIBS="-lz $LIBS"
+ AC_DEFINE(HAVE_ZLIB,[],[whether we have zlib])
+fi
+