-//TODO: signal(sid, f) is the same? then why?
-extern void sig_catch(int,void (*)(int));
-//#define sig_ignore(s) (sig_catch((s), SIG_IGN))
-//#define sig_uncatch(s) (sig_catch((s), SIG_DFL))
-extern void sig_block(int);
-extern void sig_unblock(int);
-/* UNUSED: extern void sig_blocknone(void); */
-extern void sig_pause(void);
+
+enum {
+ /* bb_signals(BB_FATAL_SIGS, handler) catches all signals which
+ * otherwise would kill us, except for those resulting from bugs:
+ * SIGSEGV, SIGILL, SIGFPE.
+ * Other fatal signals not included (TODO?):
+ * SIGBUS Bus error (bad memory access)
+ * SIGPOLL Pollable event. Synonym of SIGIO
+ * SIGPROF Profiling timer expired
+ * SIGSYS Bad argument to routine
+ * SIGTRAP Trace/breakpoint trap
+ *
+ * The only known arch with some of these sigs not fitting
+ * into 32 bits is parisc (SIGXCPU=33, SIGXFSZ=34, SIGSTKFLT=36).
+ * Dance around with long long to guard against that...
+ */
+ BB_FATAL_SIGS = (int)(0
+ + (1LL << SIGHUP)
+ + (1LL << SIGINT)
+ + (1LL << SIGTERM)
+ + (1LL << SIGPIPE) // Write to pipe with no readers
+ + (1LL << SIGQUIT) // Quit from keyboard
+ + (1LL << SIGABRT) // Abort signal from abort(3)
+ + (1LL << SIGALRM) // Timer signal from alarm(2)
+ + (1LL << SIGVTALRM) // Virtual alarm clock
+ + (1LL << SIGXCPU) // CPU time limit exceeded
+ + (1LL << SIGXFSZ) // File size limit exceeded
+ + (1LL << SIGUSR1) // Yes kids, these are also fatal!
+ + (1LL << SIGUSR2)
+ + 0),
+};
+void bb_signals(int sigs, void (*f)(int));
+/* Unlike signal() and bb_signals, sets handler with sigaction()
+ * and in a way that while signal handler is run, no other signals
+ * will be blocked: */
+void bb_signals_recursive(int sigs, void (*f)(int));
+/* syscalls like read() will be interrupted with EINTR: */
+void signal_no_SA_RESTART_empty_mask(int sig, void (*handler)(int));
+/* syscalls like read() won't be interrupted (though select/poll will be): */
+void signal_SA_RESTART_empty_mask(int sig, void (*handler)(int));
+void wait_for_any_sig(void);
+void kill_myself_with_sig(int sig) ATTRIBUTE_NORETURN;
+void sig_block(int sig);
+void sig_unblock(int sig);
+/* Will do sigaction(signum, act, NULL): */
+int sigaction_set(int sig, const struct sigaction *act);
+/* SIG_BLOCK/SIG_UNBLOCK all signals: */
+int sigprocmask_allsigs(int how);