AC_SEARCH_LIBS(gzopen,z,,[PSPP_OPTIONAL_PREREQ([zlib]); gnm_support=no;])
AC_CHECK_HEADERS(zlib.h,,[PSPP_OPTIONAL_PREREQ([zlib]); gnm_support=no;])
AC_SEARCH_LIBS(gzopen,z,,[PSPP_OPTIONAL_PREREQ([zlib]); gnm_support=no;])
AC_CHECK_HEADERS(zlib.h,,[PSPP_OPTIONAL_PREREQ([zlib]); gnm_support=no;])