getmntdirbackward (const char *name, struct mntentchn *mcprev) {
	struct mntentchn *mc, *mc0;

	mc0 = mtab_head();
	if (!mcprev)
		mcprev = mc0;
	for (mc = mcprev->prev; mc && mc != mc0; mc = mc->prev)
		if (streq(mc->m.mnt_dir, name))
			return mc;
	return NULL;
}
getmntdirbackward (const char *name, struct mntentchn *mcprev) {
	struct mntentchn *mc, *mc0;

	mc0 = mtab_head();
	if (!mcprev)
		mcprev = mc0;
	for (mc = mcprev->prev; mc && mc != mc0; mc = mc->prev)
		if (streq(mc->m.mnt_dir, name))
			return mc;
	return NULL;
}