+enum { SIGNAL_NAME_BUFSIZE = 7 + INT_STRLEN(int) + 1 };
+const char *signal_name(int signum, char *namebuf, size_t bufsize);
+
+void xsigaction(int signum, const struct sigaction *, struct sigaction *old);
+void xpthread_sigmask(int how, const sigset_t *, sigset_t *old);
+