--- libev/ev.pod	2011/07/12 23:32:10	1.379
+++ libev/ev.pod	2012/05/04 20:47:27	1.411
@@ -176,7 +176,7 @@
 Returns the current time as libev would use it. Please note that the
 C<ev_now> function is usually faster and also often returns the timestamp
 you actually want to know. Also interesting is the combination of
-C<ev_update_now> and C<ev_now>.
+C<ev_now_update> and C<ev_now>.
 
 =item ev_sleep (ev_tstamp interval)
 
@@ -249,7 +249,7 @@
 
 See the description of C<ev_embed> watchers for more info.
 
-=item ev_set_allocator (void *(*cb)(void *ptr, long size))
+=item ev_set_allocator (void *(*cb)(void *ptr, long size) throw ())
 
 Sets the allocation function to use (the prototype is similar - the
 semantics are identical to the C<realloc> C89/SuS/POSIX function). It is
@@ -285,7 +285,7 @@
    ...
    ev_set_allocator (persistent_realloc);
 
-=item ev_set_syserr_cb (void (*cb)(const char *msg))
+=item ev_set_syserr_cb (void (*cb)(const char *msg) throw ())
 
 Set the callback function to call on a retryable system call error (such
 as failed select, poll, epoll_wait). The message is a printable string
@@ -569,9 +569,9 @@
 kernel is more efficient (which says nothing about its actual speed, of
 course). While stopping, setting and starting an I/O watcher does never
 cause an extra system call as with C<EVBACKEND_EPOLL>, it still adds up to
-two event changes per incident. Support for C<fork ()> is very bad (but
-sane, unlike epoll) and it drops fds silently in similarly hard-to-detect
-cases
+two event changes per incident. Support for C<fork ()> is very bad (you
+might have to leak fd's on fork, but it's more sane than epoll) and it
+drops fds silently in similarly hard-to-detect cases
 
 This backend usually performs well under most conditions.
 
@@ -794,18 +794,22 @@
 Calling C<ev_suspend>/C<ev_resume> has the side effect of updating the
 event loop time (see C<ev_now_update>).
 
-=item ev_run (loop, int flags)
+=item bool ev_run (loop, int flags)
 
 Finally, this is it, the event handler. This function usually is called
 after you have initialised all your watchers and you want to start
 handling events. It will ask the operating system for any new events, call
-the watcher callbacks, an then repeat the whole process indefinitely: This
+the watcher callbacks, and then repeat the whole process indefinitely: This
 is why event loops are called I<loops>.
 
 If the flags argument is specified as C<0>, it will keep handling events
 until either no event watchers are active anymore or C<ev_break> was
 called.
 
+The return value is false if there are no more active watchers (which
+usually means "all jobs done" or "deadlock"), and true in all other cases
+(which usually means " you should call C<ev_run> again").
+
 Please note that an explicit C<ev_break> is usually better than
 relying on all watchers to be stopped when deciding when a program has
 finished (especially in interactive programs), but having a program
@@ -813,8 +817,8 @@
 of relying on its watchers stopping correctly, that is truly a thing of
 beauty.
 
-This function is also I<mostly> exception-safe - you can break out of
-a C<ev_run> call by calling C<longjmp> in a callback, throwing a C++
+This function is I<mostly> exception-safe - you can break out of a
+C<ev_run> call by calling C<longjmp> in a callback, throwing a C++
 exception and so on. This does not decrement the C<ev_depth> value, nor
 will it clear any outstanding C<EVBREAK_ONE> breaks.
 
@@ -1014,7 +1018,7 @@
 If you want to reset the callback, use C<ev_invoke_pending> as new
 callback.
 
-=item ev_set_loop_release_cb (loop, void (*release)(EV_P), void (*acquire)(EV_P))
+=item ev_set_loop_release_cb (loop, void (*release)(EV_P) throw (), void (*acquire)(EV_P) throw ())
 
 Sometimes you want to share the same loop between multiple threads. This
 can be done relatively simply by putting mutex_lock/unlock calls around
@@ -1022,7 +1026,7 @@
 
 However, C<ev_run> can run an indefinite time, so it is not feasible
 to wait for it to return. One way around this is to wake up the event
-loop via C<ev_break> and C<av_async_send>, another way is to set these
+loop via C<ev_break> and C<ev_async_send>, another way is to set these
 I<release> and I<acquire> callbacks on the loop.
 
 When set, then C<release> will be called just before the thread is
@@ -1172,13 +1176,18 @@
 
 =item C<EV_CHECK>
 
-All C<ev_prepare> watchers are invoked just I<before> C<ev_run> starts
-to gather new events, and all C<ev_check> watchers are invoked just after
-C<ev_run> has gathered them, but before it invokes any callbacks for any
-received events. Callbacks of both watcher types can start and stop as
-many watchers as they want, and all of them will be taken into account
-(for example, a C<ev_prepare> watcher might start an idle watcher to keep
-C<ev_run> from blocking).
+All C<ev_prepare> watchers are invoked just I<before> C<ev_run> starts to
+gather new events, and all C<ev_check> watchers are queued (not invoked)
+just after C<ev_run> has gathered them, but before it queues any callbacks
+for any received events. That means C<ev_prepare> watchers are the last
+watchers invoked before the event loop sleeps or polls for new events, and
+C<ev_check> watchers will be invoked before any other watchers of the same
+or lower priority within an event loop iteration.
+
+Callbacks of both watcher types can start and stop as many watchers as
+they want, and all of them will be taken into account (for example, a
+C<ev_prepare> watcher might start an idle watcher to keep C<ev_run> from
+blocking).
 
 =item C<EV_EMBED>
 
@@ -1311,7 +1320,7 @@
 
 Returns the callback currently set on the watcher.
 
-=item ev_cb_set (ev_TYPE *watcher, callback)
+=item ev_set_cb (ev_TYPE *watcher, callback)
 
 Change the callback. You can change the callback at virtually any time
 (modulo threads).
@@ -1773,10 +1782,11 @@
 
 The callback is guaranteed to be invoked only I<after> its timeout has
 passed (not I<at>, so on systems with very low-resolution clocks this
-might introduce a small delay). If multiple timers become ready during the
-same loop iteration then the ones with earlier time-out values are invoked
-before ones of the same priority with later time-out values (but this is
-no longer true when a callback calls C<ev_run> recursively).
+might introduce a small delay, see "the special problem of being too
+early", below). If multiple timers become ready during the same loop
+iteration then the ones with earlier time-out values are invoked before
+ones of the same priority with later time-out values (but this is no
+longer true when a callback calls C<ev_run> recursively).
 
 =head3 Be smart about timeouts
 
@@ -1861,63 +1871,77 @@
 but remember the time of last activity, and check for a real timeout only
 within the callback:
 
+   ev_tstamp timeout = 60.;
    ev_tstamp last_activity; // time of last activity
+   ev_timer timer;
 
    static void
    callback (EV_P_ ev_timer *w, int revents)
    {
-     ev_tstamp now     = ev_now (EV_A);
-     ev_tstamp timeout = last_activity + 60.;
+     // calculate when the timeout would happen
+     ev_tstamp after = last_activity - ev_now (EV_A) + timeout;
 
-     // if last_activity + 60. is older than now, we did time out
-     if (timeout < now)
+     // if negative, it means we the timeout already occurred
+     if (after < 0.)
        {
          // timeout occurred, take action
        }
      else
        {
-         // callback was invoked, but there was some activity, re-arm
-         // the watcher to fire in last_activity + 60, which is
-         // guaranteed to be in the future, so "again" is positive:
-         w->repeat = timeout - now;
-         ev_timer_again (EV_A_ w);
+         // callback was invoked, but there was some recent 
+         // activity. simply restart the timer to time out
+         // after "after" seconds, which is the earliest time
+         // the timeout can occur.
+         ev_timer_set (w, after, 0.);
+         ev_timer_start (EV_A_ w);
        }
    }
 
-To summarise the callback: first calculate the real timeout (defined
-as "60 seconds after the last activity"), then check if that time has
-been reached, which means something I<did>, in fact, time out. Otherwise
-the callback was invoked too early (C<timeout> is in the future), so
-re-schedule the timer to fire at that future time, to see if maybe we have
-a timeout then.
-
-Note how C<ev_timer_again> is used, taking advantage of the
-C<ev_timer_again> optimisation when the timer is already running.
+To summarise the callback: first calculate in how many seconds the
+timeout will occur (by calculating the absolute time when it would occur,
+C<last_activity + timeout>, and subtracting the current time, C<ev_now
+(EV_A)> from that).
+
+If this value is negative, then we are already past the timeout, i.e. we
+timed out, and need to do whatever is needed in this case.
+
+Otherwise, we now the earliest time at which the timeout would trigger,
+and simply start the timer with this timeout value.
+
+In other words, each time the callback is invoked it will check whether
+the timeout occurred. If not, it will simply reschedule itself to check
+again at the earliest time it could time out. Rinse. Repeat.
 
 This scheme causes more callback invocations (about one every 60 seconds
 minus half the average time between activity), but virtually no calls to
 libev to change the timeout.
 
-To start the timer, simply initialise the watcher and set C<last_activity>
-to the current time (meaning we just have some activity :), then call the
-callback, which will "do the right thing" and start the timer:
-
-   ev_init (timer, callback);
-   last_activity = ev_now (loop);
-   callback (loop, timer, EV_TIMER);
+To start the machinery, simply initialise the watcher and set
+C<last_activity> to the current time (meaning there was some activity just
+now), then call the callback, which will "do the right thing" and start
+the timer:
+
+   last_activity = ev_now (EV_A);
+   ev_init (&timer, callback);
+   callback (EV_A_ &timer, 0);
 
-And when there is some activity, simply store the current time in
+When there is some activity, simply store the current time in
 C<last_activity>, no libev calls at all:
 
-   last_activity = ev_now (loop);
+   if (activity detected)
+     last_activity = ev_now (EV_A);
+
+When your timeout value changes, then the timeout can be changed by simply
+providing a new value, stopping the timer and calling the callback, which
+will again do the right thing (for example, time out immediately :).
+
+   timeout = new_value;
+   ev_timer_stop (EV_A_ &timer);
+   callback (EV_A_ &timer, 0);
 
 This technique is slightly more complex, but in most cases where the
 time-out is unlikely to be triggered, much more efficient.
 
-Changing the timeout is trivial as well (if it isn't hard-coded in the
-callback :) - just change the timeout and invoke the callback, which will
-fix things for you.
-
 =item 4. Wee, just use a double-linked list for your timeouts.
 
 If there is not one request, but many thousands (millions...), all
@@ -1953,10 +1977,47 @@
 off after the first million or so of active timers, i.e. it's usually
 overkill :)
 
+=head3 The special problem of being too early
+
+If you ask a timer to call your callback after three seconds, then
+you expect it to be invoked after three seconds - but of course, this
+cannot be guaranteed to infinite precision. Less obviously, it cannot be
+guaranteed to any precision by libev - imagine somebody suspending the
+process with a STOP signal for a few hours for example.
+
+So, libev tries to invoke your callback as soon as possible I<after> the
+delay has occurred, but cannot guarantee this.
+
+A less obvious failure mode is calling your callback too early: many event
+loops compare timestamps with a "elapsed delay >= requested delay", but
+this can cause your callback to be invoked much earlier than you would
+expect.
+
+To see why, imagine a system with a clock that only offers full second
+resolution (think windows if you can't come up with a broken enough OS
+yourself). If you schedule a one-second timer at the time 500.9, then the
+event loop will schedule your timeout to elapse at a system time of 500
+(500.9 truncated to the resolution) + 1, or 501.
+
+If an event library looks at the timeout 0.1s later, it will see "501 >=
+501" and invoke the callback 0.1s after it was started, even though a
+one-second delay was requested - this is being "too early", despite best
+intentions.
+
+This is the reason why libev will never invoke the callback if the elapsed
+delay equals the requested delay, but only when the elapsed delay is
+larger than the requested delay. In the example above, libev would only invoke
+the callback at system time 502, or 1.1s after the timer was started.
+
+So, while libev cannot guarantee that your callback will be invoked
+exactly when requested, it I<can> and I<does> guarantee that the requested
+delay has actually elapsed, or in other words, it always errs on the "too
+late" side of things.
+
 =head3 The special problem of time updates
 
-Establishing the current time is a costly operation (it usually takes at
-least two system calls): EV therefore updates its idea of the current
+Establishing the current time is a costly operation (it usually takes
+at least one system call): EV therefore updates its idea of the current
 time only before and after C<ev_run> collects new events, which causes a
 growing difference between C<ev_now ()> and C<ev_time ()> when handling
 lots of events in one iteration.
@@ -1973,6 +2034,39 @@
 update of the time returned by C<ev_now ()> by calling C<ev_now_update
 ()>.
 
+=head3 The special problem of unsynchronised clocks
+
+Modern systems have a variety of clocks - libev itself uses the normal
+"wall clock" clock and, if available, the monotonic clock (to avoid time
+jumps).
+
+Neither of these clocks is synchronised with each other or any other clock
+on the system, so C<ev_time ()> might return a considerably different time
+than C<gettimeofday ()> or C<time ()>. On a GNU/Linux system, for example,
+a call to C<gettimeofday> might return a second count that is one higher
+than a directly following call to C<time>.
+
+The moral of this is to only compare libev-related timestamps with
+C<ev_time ()> and C<ev_now ()>, at least if you want better precision than
+a second or so.
+
+One more problem arises due to this lack of synchronisation: if libev uses
+the system monotonic clock and you compare timestamps from C<ev_time>
+or C<ev_now> from when you started your timer and when your callback is
+invoked, you will find that sometimes the callback is a bit "early".
+
+This is because C<ev_timer>s work in real time, not wall clock time, so
+libev makes sure your callback is not invoked before the delay happened,
+I<measured according to the real time>, not the system clock.
+
+If your timeouts are based on a physical timescale (e.g. "time out this
+connection after 100 seconds") then this shouldn't bother you as it is
+exactly the right behaviour.
+
+If you want to compare wall clock/system timestamps to your timers, then
+you need to use C<ev_periodic>s, as these are based on the wall clock
+time, where your comparisons will always generate correct results.
+
 =head3 The special problems of suspended animation
 
 When you leave the server world it is quite customary to hit machines that
@@ -2025,15 +2119,24 @@
 
 =item ev_timer_again (loop, ev_timer *)
 
-This will act as if the timer timed out and restarts it again if it is
-repeating. The exact semantics are:
+This will act as if the timer timed out, and restarts it again if it is
+repeating. It basically works like calling C<ev_timer_stop>, updating the
+timeout to the C<repeat> value and calling C<ev_timer_start>.
 
-If the timer is pending, its pending status is cleared.
+The exact semantics are as in the following rules, all of which will be
+applied to the watcher:
+
+=over 4
 
-If the timer is started but non-repeating, stop it (as if it timed out).
+=item If the timer is pending, the pending status is always cleared.
 
-If the timer is repeating, either start it if necessary (with the
-C<repeat> value), or reset the running timer to the C<repeat> value.
+=item If the timer is started but non-repeating, stop it (as if it timed
+out, without invoking it).
+
+=item If the timer is repeating, make the C<repeat> value the new timeout
+and start the timer, if necessary.
+
+=back
 
 This sounds a bit complicated, see L<Be smart about timeouts>, above, for a
 usage example.
@@ -2746,6 +2849,20 @@
 "pseudo-background processing", or delay processing stuff to after the
 event loop has handled all outstanding events.
 
+=head3 Abusing an C<ev_idle> watcher for its side-effect
+
+As long as there is at least one active idle watcher, libev will never
+sleep unnecessarily. Or in other words, it will loop as fast as possible.
+For this to work, the idle watcher doesn't need to be invoked at all - the
+lowest priority will do.
+
+This mode of operation can be useful together with an C<ev_check> watcher,
+to do something on each event loop iteration - for example to balance load
+between different connections.
+
+See L<Abusing an ev_check watcher for its side-effect> for a longer
+example.
+
 =head3 Watcher-Specific Functions and Data Members
 
 =over 4
@@ -2766,7 +2883,12 @@
    static void
    idle_cb (struct ev_loop *loop, ev_idle *w, int revents)
    {
+     // stop the watcher
+     ev_idle_stop (loop, w);
+
+     // now we can free it
      free (w);
+
      // now do something you wanted to do when the program has
      // no longer anything immediate to do.
    }
@@ -2778,7 +2900,7 @@
 
 =head2 C<ev_prepare> and C<ev_check> - customise your event loop!
 
-Prepare and check watchers are usually (but not always) used in pairs:
+Prepare and check watchers are often (but not always) used in pairs:
 prepare watchers get invoked before the process blocks and check watchers
 afterwards.
 
@@ -2816,9 +2938,10 @@
 loop from blocking if lower-priority coroutines are active, thus mapping
 low-priority coroutines to idle/background tasks).
 
-It is recommended to give C<ev_check> watchers highest (C<EV_MAXPRI>)
-priority, to ensure that they are being run before any other watchers
-after the poll (this doesn't matter for C<ev_prepare> watchers).
+When used for this purpose, it is recommended to give C<ev_check> watchers
+highest (C<EV_MAXPRI>) priority, to ensure that they are being run before
+any other watchers after the poll (this doesn't matter for C<ev_prepare>
+watchers).
 
 Also, C<ev_check> watchers (and C<ev_prepare> watchers, too) should not
 activate ("feed") events into libev. While libev fully supports this, they
@@ -2828,6 +2951,26 @@
 C<ev_check> watcher ran (always remind yourself to coexist peacefully with
 others).
 
+=head3 Abusing an C<ev_check> watcher for its side-effect
+
+C<ev_check> (and less often also C<ev_prepare>) watchers can also be
+useful because they are called once per event loop iteration. For
+example, if you want to handle a large number of connections fairly, you
+normally only do a bit of work for each active connection, and if there
+is more work to do, you wait for the next event loop iteration, so other
+connections have a chance of making progress.
+
+Using an C<ev_check> watcher is almost enough: it will be called on the
+next event loop iteration. However, that isn't as soon as possible -
+without external events, your C<ev_check> watcher will not be invoked.
+
+
+This is where C<ev_idle> watchers come in handy - all you need is a
+single global idle watcher that is active as long as you have one active
+C<ev_check> watcher. The C<ev_idle> watcher makes sure the event loop
+will not sleep, and the C<ev_check> watcher makes sure a callback gets
+invoked. Neither watcher alone can do that.
+
 =head3 Watcher-Specific Functions and Data Members
 
 =over 4
@@ -3217,7 +3360,7 @@
 This functionality is very similar to C<ev_signal> watchers, as signals,
 too, are asynchronous in nature, and signals, too, will be compressed
 (i.e. the number of callback invocations may be less than the number of
-C<ev_async_sent> calls). In fact, you could use signal watchers as a kind
+C<ev_async_send> calls). In fact, you could use signal watchers as a kind
 of "global async watchers" by using a watcher on an otherwise unused
 signal, and C<ev_feed_signal> to signal this watcher from another thread,
 even without knowing which loop owns the signal.
@@ -3404,7 +3547,7 @@
 =item ev_feed_fd_event (loop, int fd, int revents)
 
 Feed an event on the given fd, as if a file descriptor backend detected
-the given events it.
+the given events.
 
 =item ev_feed_signal_event (loop, int signum)
 
@@ -3488,6 +3631,46 @@
        (((char *)w) - offsetof (struct my_biggy, t2));
    }
 
+=head2 AVOIDING FINISHING BEFORE RETURNING
+
+Often you have structures like this in event-based programs:
+
+  callback ()
+  {
+    free (request);
+  }
+
+  request = start_new_request (..., callback);
+
+The intent is to start some "lengthy" operation. The C<request> could be
+used to cancel the operation, or do other things with it.
+
+It's not uncommon to have code paths in C<start_new_request> that
+immediately invoke the callback, for example, to report errors. Or you add
+some caching layer that finds that it can skip the lengthy aspects of the
+operation and simply invoke the callback with the result.
+
+The problem here is that this will happen I<before> C<start_new_request>
+has returned, so C<request> is not set.
+
+Even if you pass the request by some safer means to the callback, you
+might want to do something to the request after starting it, such as
+canceling it, which probably isn't working so well when the callback has
+already been invoked.
+
+A common way around all these issues is to make sure that
+C<start_new_request> I<always> returns before the callback is invoked. If
+C<start_new_request> immediately knows the result, it can artificially
+delay invoking the callback by e.g. using a C<prepare> or C<idle> watcher
+for example, or more sneakily, by reusing an existing (stopped) watcher
+and pushing it into the pending queue:
+
+   ev_set_cb (watcher, callback);
+   ev_feed_event (EV_A_ watcher, 0);
+
+This way, C<start_new_request> can safely return before the callback is
+invoked, while not delaying callback invocation too much.
+
 =head2 MODEL/NESTED EVENT LOOP INVOCATIONS AND EXIT CONDITIONS
 
 Often (especially in GUI toolkits) there are places where you have
@@ -3510,7 +3693,7 @@
    while (!exit_main_loop)
      ev_run (EV_DEFAULT_ EVRUN_ONCE);
 
-   // in a model watcher
+   // in a modal watcher
    int exit_nested_loop = 0;
 
    while (!exit_nested_loop)
@@ -3694,13 +3877,13 @@
    void
    wait_for_event (ev_watcher *w)
    {
-     ev_cb_set (w) = current_coro;
+     ev_set_cb (w, current_coro);
      switch_to (libev_coro);
    }
 
 That basically suspends the coroutine inside C<wait_for_event> and
 continues the libev coroutine, which, when appropriate, switches back to
-this or any other coroutine. I am sure if you sue this your own :)
+this or any other coroutine.
 
 You can do similar tricks if you have, say, threads with an event queue -
 instead of storing a coroutine, you store the queue object and instead of
@@ -3761,6 +3944,39 @@
 
 =head1 C++ SUPPORT
 
+=head2 C API
+
+The normal C API should work fine when used from C++: both ev.h and the
+libev sources can be compiled as C++. Therefore, code that uses the C API
+will work fine.
+
+Proper exception specifications might have to be added to callbacks passed
+to libev: exceptions may be thrown only from watcher callbacks, all
+other callbacks (allocator, syserr, loop acquire/release and periodioc
+reschedule callbacks) must not throw exceptions, and might need a C<throw
+()> specification. If you have code that needs to be compiled as both C
+and C++ you can use the C<EV_THROW> macro for this:
+
+   static void
+   fatal_error (const char *msg) EV_THROW
+   {
+     perror (msg);
+     abort ();
+   }
+
+   ...
+   ev_set_syserr_cb (fatal_error);
+
+The only API functions that can currently throw exceptions are C<ev_run>,
+C<ev_invoke>, C<ev_invoke_pending> and C<ev_loop_destroy> (the latter
+because it runs cleanup watchers).
+
+Throwing exceptions in watcher callbacks is only supported if libev itself
+is compiled with a C++ compiler or your C and C++ environments allow
+throwing exceptions through C libraries (most do).
+
+=head2 C++ API
+
 Libev comes with some simplistic wrapper classes for C++ that mainly allow
 you to use some convenience methods to start/stop watchers and also change
 the callback model to a model using method callbacks on objects.
@@ -3785,6 +4001,10 @@
 you need support for other types of functors please contact the author
 (preferably after implementing it).
 
+For all this to work, your C++ compiler either has to use the same calling
+conventions as your C compiler (for static member functions), or you have
+to embed libev and compile libev itself as C++.
+
 Here is a list of things available in the C<ev> namespace:
 
 =over 4
@@ -3803,7 +4023,7 @@
 For each C<ev_TYPE> watcher in F<ev.h> there is a corresponding class of
 the same name in the C<ev> namespace, with the exception of C<ev_signal>
 which is called C<ev::sig> to avoid clashes with the C<signal> macro
-defines by many implementations.
+defined by many implementations.
 
 All of those classes have these methods:
 
@@ -4065,7 +4285,11 @@
 =item C<EV_DEFAULT>, C<EV_DEFAULT_>
 
 Similar to the other two macros, this gives you the value of the default
-loop, if multiple loops are supported ("ev loop default").
+loop, if multiple loops are supported ("ev loop default"). The default loop
+will be initialised if it isn't already initialised.
+
+For non-multiplicity builds, these macros do nothing, so you always have
+to initialise the loop somewhere.
 
 =item C<EV_DEFAULT_UC>, C<EV_DEFAULT_UC_>
 
@@ -4368,6 +4592,19 @@
 be detected at runtime. If undefined, it will be enabled if the headers
 indicate GNU/Linux + Glibc 2.4 or newer, otherwise disabled.
 
+=item EV_NO_SMP
+
+If defined to be C<1>, libev will assume that memory is always coherent
+between threads, that is, threads can be used, but threads never run on
+different cpus (or different cpu cores). This reduces dependencies
+and makes libev faster.
+
+=item EV_NO_THREADS
+
+If defined to be C<1>, libev will assume that it will never be called
+from different threads, which is a stronger assumption than C<EV_NO_SMP>,
+above. This reduces dependencies and makes libev faster.
+
 =item EV_ATOMIC_T
 
 Libev requires an integer type (suitable for storing C<0> or C<1>) whose
@@ -4414,6 +4651,10 @@
 for multiple event loops and there is no first event loop pointer
 argument. Instead, all functions act on the single default loop.
 
+Note that C<EV_DEFAULT> and C<EV_DEFAULT_> will no longer provide a
+default loop when multiplicity is switched off - you always have to
+initialise the loop manually in this case.
+
 =item EV_MINPRI
 
 =item EV_MAXPRI
@@ -4459,7 +4700,7 @@
    #define EV_ASYNC_ENABLE 1
 
 The actual value is a bitset, it can be a combination of the following
-values:
+values (by default, all of these are enabled):
 
 =over 4
 
@@ -4474,6 +4715,9 @@
 gcc is recommended, as well as C<-DNDEBUG>, as libev contains a number of
 assertions.
 
+The default is off when C<__OPTIMIZE_SIZE__> is defined by your compiler
+(e.g. gcc with C<-Os>).
+
 =item C<2> - faster/larger data structures
 
 Replaces the small 2-heap for timer management by a faster 4-heap, larger
@@ -4481,6 +4725,9 @@
 and can additionally have an effect on the size of data structures at
 runtime.
 
+The default is off when C<__OPTIMIZE_SIZE__> is defined by your compiler
+(e.g. gcc with C<-Os>).
+
 =item C<4> - full API configuration
 
 This enables priorities (sets C<EV_MAXPRI>=2 and C<EV_MINPRI>=-2), and
@@ -4521,6 +4768,20 @@
 your program might be left out as well - a binary starting a timer and an
 I/O watcher then might come out at only 5Kb.
 
+=item EV_API_STATIC
+
+If this symbol is defined (by default it is not), then all identifiers
+will have static linkage. This means that libev will not export any
+identifiers, and you cannot link against libev anymore. This can be useful
+when you embed libev, only want to use libev functions in a single file,
+and do not want its identifiers to be visible.
+
+To use this, define C<EV_API_STATIC> and include F<ev.c> in the file that
+wants to use libev.
+
+This option only works when libev is compiled with a C compiler, as C++
+doesn't support the required declaration syntax.
+
 =item EV_AVOID_STDIO
 
 If this is set to C<1> at compiletime, then libev will avoid using stdio
@@ -5055,7 +5316,7 @@
 implementations using IEEE 754, which is basically all existing ones.
 
 With IEEE 754 doubles, you get microsecond accuracy until at least the
-year 2255 (and millisecond accuray till the year 287396 - by then, libev
+year 2255 (and millisecond accuracy till the year 287396 - by then, libev
 is either obsolete or somebody patched it to use C<long double> or
 something like that, just kidding).