+AC_CHECK_FUNCS(strndup strlcpy getpwuid_r strtok_r rewinddir vasprintf)
+AM_CONDITIONAL(NEED_VASPRINTF, test x$have_vasprintf = x )
+AC_CHECK_LIB(iconv, iconv_open, LIBS="$LIBS -liconv")
+AC_CHECK_LIB(iconv, libiconv_open, LIBS="$LIBS -liconv")
+AC_CHECK_LIB(iconv, iconv_open, ICONV_LIBS="-liconv")
+AC_CHECK_LIB(iconv, libiconv_open, ICONV_LIBS="-liconv")
+AC_SUBST(ICONV_LIBS)
+LIBS="$LIBS $ICONV_LIBS"
+AC_SEARCH_LIBS(sqrtf, m)
+
+# nanosleep may not be part of libc, also search it in other libraries
+AC_SEARCH_LIBS(nanosleep, rt)
+
+AC_SEARCH_LIBS(dlopen, dl)
+old_ldflags="${LDFLAGS}"
+LDFLAGS="${LDFLAGS} -Wl,-export-dynamic"
+AC_TRY_LINK(, [int i;], found_export_dynamic=yes, found_export_dynamic=no)
+if test $found_export_dynamic = no; then
+ LDFLAGS="${old_ldflags}"
+fi
+
+AC_MSG_CHECKING(for varargs macros)
+AC_TRY_COMPILE([],[
+int foo (int i, int j);
+#define bar(...) foo (1, __VA_ARGS__)
+void main () {
+ bar (2);
+}
+],have_iso_varargs=yes,have_iso_varargs=no)
+AC_MSG_RESULT($have_iso_varargs)
+G_HAVE_ISO_VARARGS=0
+if test "x$have_iso_varargs" = "xyes"; then
+ G_HAVE_ISO_VARARGS=1
+fi
+AC_SUBST(G_HAVE_ISO_VARARGS)
+
+AC_CHECK_HEADERS(getopt.h sys/time.h sys/wait.h pwd.h langinfo.h iconv.h)