--- libev/ev.pod	2011/01/11 10:56:01	1.359
+++ libev/ev.pod	2011/01/17 12:11:12	1.360
@@ -444,6 +444,9 @@
 want to handle signals only in specific threads and want to avoid libev
 unblocking the signals.
 
+It's also required by POSIX in a threaded program, as libev calls
+C<sigprocmask>, whose behaviour is officially unspecified.
+
 This flag's behaviour will become the default in future versions of libev.
 
 =item C<EVBACKEND_SELECT>  (value 1, portable select backend)
@@ -2302,7 +2305,8 @@
 Both the signal mask (C<sigprocmask>) and the signal disposition
 (C<sigaction>) are unspecified after starting a signal watcher (and after
 stopping it again), that is, libev might or might not block the signal,
-and might or might not set or restore the installed signal handler.
+and might or might not set or restore the installed signal handler (but
+see C<EVFLAG_NOSIGMASK>).
 
 While this does not matter for the signal disposition (libev never
 sets signals to C<SIG_IGN>, so handlers will be reset to C<SIG_DFL> on