rem: return vfs_open_dir(path, false);
add: return dir_open(path, false);
context: user_open_dir(const char *upath){	char path[SYS_MAX_PATH_LEN];	int rc;	if ((addr)upath >= KERNEL_BASE && (addr)upath <= KERNEL_TOP)		return ERR_VM_BAD_USER_MEMORY;	rc = user_strncpy(path, upath, SYS_MAX_PATH_LEN-1);	if (rc < 0)		return rc;	path[SYS_MAX_PATH_LEN-1] = 0;	return vfs_open_dir(path, false);}