+bool null_or_empty(struct stat *st);
+int null_or_empty_path(const char *fn);
+
+DIR *xopendirat(int dirfd, const char *name, int flags);
+
+void dual_timestamp_serialize(FILE *f, const char *name, dual_timestamp *t);
+void dual_timestamp_deserialize(const char *value, dual_timestamp *t);
+
+char *fstab_node_to_udev_node(const char *p);
+
+void filter_environ(const char *prefix);
+
+bool tty_is_vc(const char *tty);
+int vtnr_from_tty(const char *tty);
+const char *default_term_for_tty(const char *tty);
+
+int detect_vm(const char **id);
+int detect_container(const char **id);
+int detect_virtualization(const char **id);
+
+void execute_directory(const char *directory, DIR *_d, char *argv[]);
+
+int kill_and_sigcont(pid_t pid, int sig);
+
+bool nulstr_contains(const char*nulstr, const char *needle);
+
+bool plymouth_running(void);
+
+void parse_syslog_priority(char **p, int *priority);
+
+int have_effective_cap(int value);
+
+bool hostname_is_valid(const char *s);
+char* hostname_cleanup(char *s);
+
+char* strshorten(char *s, size_t l);
+
+int terminal_vhangup_fd(int fd);
+int terminal_vhangup(const char *name);
+
+int vt_disallocate(const char *name);
+
+int copy_file(const char *from, const char *to);
+int symlink_or_copy(const char *from, const char *to);
+int symlink_or_copy_atomic(const char *from, const char *to);
+
+int fchmod_umask(int fd, mode_t mode);
+
+int conf_files_list(char ***strv, const char *suffix, const char *dir, ...);
+
+int hwclock_is_localtime(void);
+int hwclock_apply_localtime_delta(int *min);
+int hwclock_reset_localtime_delta(void);
+int hwclock_get_time(struct tm *tm);
+int hwclock_set_time(const struct tm *tm);
+
+int audit_session_from_pid(pid_t pid, uint32_t *id);
+
+bool display_is_local(const char *display);
+int socket_from_display(const char *display, char **path);
+
+int get_user_creds(const char **username, uid_t *uid, gid_t *gid, const char **home);
+
+int glob_exists(const char *path);
+
+int dirent_ensure_type(DIR *d, struct dirent *de);
+
+int in_search_path(const char *path, char **search);
+
+#define NULSTR_FOREACH(i, l) \