extern int uptime_main(int argc, char** argv);
extern int uniq_main(int argc, char** argv);
extern int update_main(int argc, char** argv);
+extern int usleep_main(int argc, char** argv);
extern int wc_main(int argc, char** argv);
extern int whoami_main(int argc, char** argv);
extern int yes_main(int argc, char** argv);