+block_signals (setp, osetp)
+ sigset_t *setp, *osetp;
+{
+#ifdef HAVE_POSIX_SIGNALS
+ sigfillset (setp);
+ sigemptyset (osetp);
+ sigprocmask (SIG_BLOCK, setp, osetp);
+#else
+# if defined (HAVE_BSD_SIGNALS)
+ *osetp = sigsetmask (-1);
+# endif
+#endif
+}
+
+static void
+unblock_signals (setp, osetp)
+ sigset_t *setp, *osetp;
+{
+#ifdef HAVE_POSIX_SIGNALS
+ sigprocmask (SIG_SETMASK, osetp, (sigset_t *)NULL);
+#else
+# if defined (HAVE_BSD_SIGNALS)
+ sigsetmask (*osetp);
+# endif
+#endif
+}
+
+static void