[ViewVC] Diff of: cvs/libev/ev.pod

Comparing libev/ev.pod (file contents):
Revision 1.289 by root, Tue Mar 16 17:11:49 2010 UTC vs.
Revision 1.291 by root, Tue Mar 16 20:32:20 2010 UTC

 useful to try out specific backends to test their performance, or to work
 around bugs.
 =item C<EVFLAG_FORKCHECK>
-Instead of calling C<ev_default_fork> or C<ev_loop_fork> manually after
+Instead of calling C<ev_loop_fork> manually after a fork, you can also
-a fork, you can also make libev check for a fork in each iteration by
+make libev check for a fork in each iteration by enabling this flag.
-enabling this flag.
 This works by calling C<getpid ()> on every iteration of the loop,
 and thus this might slow down your event loop if you do a lot of loop
 iterations and little real work, but is usually not noticeable (on my
 GNU/Linux system for example, C<getpid> is actually a simple 5-insn sequence
    ev_default_loop (ev_recommended_backends () | EVBACKEND_KQUEUE);
 =item struct ev_loop *ev_loop_new (unsigned int flags)
 Similar to C<ev_default_loop>, but always creates a new event loop that is
-always distinct from the default loop. Unlike the default loop, it cannot
+always distinct from the default loop.
-handle signal and child watchers, and attempts to do so will be greeted by
-undefined behaviour (or a failed assertion if assertions are enabled).
-Note that this function I<is> thread-safe, and the recommended way to use
+Note that this function I<is> thread-safe, and one common way to use
 libev with threads is indeed to create one loop per thread, and using the
 default loop in the "main" or "initial" thread.
 Example: Try to create a event loop that uses epoll and nothing else.
    if (!epoller)
      fatal ("no epoll found here, maybe it hides under your chair");
 =item ev_default_destroy ()
-Destroys the default loop again (frees all memory and kernel state
+Destroys the default loop (frees all memory and kernel state etc.). None
-etc.). None of the active event watchers will be stopped in the normal
+of the active event watchers will be stopped in the normal sense, so
-sense, so e.g. C<ev_is_active> might still return true. It is your
+e.g. C<ev_is_active> might still return true. It is your responsibility to
-responsibility to either stop all watchers cleanly yourself I<before>
+either stop all watchers cleanly yourself I<before> calling this function,
-calling this function, or cope with the fact afterwards (which is usually
+or cope with the fact afterwards (which is usually the easiest thing, you
-the easiest thing, you can just ignore the watchers and/or C<free ()> them
+can just ignore the watchers and/or C<free ()> them for example).
-for example).
 Note that certain global state, such as signal state (and installed signal
 handlers), will not be freed by this function, and related watchers (such
 as signal and child watchers) would need to be stopped manually.
 name, you can call it anytime, but it makes most sense after forking, in
 the child process (or both child and parent, but that again makes little
 sense). You I<must> call it in the child before using any of the libev
 functions, and it will only take effect at the next C<ev_loop> iteration.
+Again, you I<have> to call it on I<any> loop that you want to re-use after
+a fork, I<even if you do not plan to use the loop in the parent>. This is
+because some kernel interfaces *cough* I<kqueue> *cough* do funny things
+during fork.
 On the other hand, you only need to call this function in the child
-process if and only if you want to use the event library in the child. If
+process if and only if you want to use the event loop in the child. If you
-you just fork+exec, you don't have to call it at all.
+just fork+exec or create a new loop in the child, you don't have to call
+it at all.
 The function itself is quite fast and it's usually not a problem to call
 it just in case after a fork. To make this easy, the function will fit in
 quite nicely into a call to C<pthread_atfork>:
 =item ev_loop_fork (loop)
 Like C<ev_default_fork>, but acts on an event loop created by
 C<ev_loop_new>. Yes, you have to call this on every allocated event loop
-after fork that you want to re-use in the child, and how you do this is
+after fork that you want to re-use in the child, and how you keep track of
-entirely your own problem.
+them is entirely your own problem.
 =item int ev_is_default_loop (loop)
 Returns true when the given loop is, in fact, the default loop, and false
 otherwise.
-=item unsigned int ev_loop_count (loop)
+=item unsigned int ev_iteration (loop)
-Returns the count of loop iterations for the loop, which is identical to
+Returns the current iteration count for the loop, which is identical to
 the number of times libev did poll for new events. It starts at C<0> and
 happily wraps around with enough iterations.
 This value can sometimes be useful as a generation counter of sorts (it
 "ticks" the number of loop iterations), as it roughly corresponds with
-C<ev_prepare> and C<ev_check> calls.
+C<ev_prepare> and C<ev_check> calls - and is incremented between the
+prepare and check phases.
-=item unsigned int ev_loop_depth (loop)
+=item unsigned int ev_depth (loop)
 Returns the number of times C<ev_loop> was entered minus the number of
 times C<ev_loop> was exited, in other words, the recursion depth.
 Outside C<ev_loop>, this number is zero. In a callback, this number is
 C<1>, unless C<ev_loop> was invoked recursively (or from another thread),
 in which case it is higher.
 Leaving C<ev_loop> abnormally (setjmp/longjmp, cancelling the thread
-etc.), doesn't count as exit.
+etc.), doesn't count as "exit" - consider this as a hint to avoid such
+ungentleman behaviour unless it's really convenient.
 =item unsigned int ev_backend (loop)
 Returns one of the C<EVBACKEND_*> flags indicating the event backend in
 use.
 involves iterating over all running async watchers or all signal numbers.
 =back
-=head1 PORTING FROM 3.X TO 4.X
+=head1 PORTING FROM LIBEV 3.X TO 4.X
 The major version 4 introduced some minor incompatible changes to the API.
+At the moment, the C<ev.h> header file tries to implement superficial
+compatibility, so most programs should still compile. Those might be
+removed in later versions of libev, so better update early than late.
 =over 4
+=item C<ev_loop_count> renamed to C<ev_iteration>
+=item C<ev_loop_depth> renamed to C<ev_depth>
+=item C<ev_loop_verify> renamed to C<ev_verify>
+Most functions working on C<struct ev_loop> objects don't have an
+C<ev_loop_> prefix, so it was removed. Note that C<ev_loop_fork> is
+still called C<ev_loop_fork> because it would otherwise clash with the
+C<ev_frok> typedef.
-=item C<EV_TIMEOUT> replaced by C<EV_TIMER> in C<revents>
+=item C<EV_TIMEOUT> renamed to C<EV_TIMER> in C<revents>
 This is a simple rename - all other watcher types use their name
 as revents flag, and now C<ev_timer> does, too.
 Both C<EV_TIMER> and C<EV_TIMEOUT> symbols were present in 3.x versions

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Comparing libev/ev.pod (file contents): Revision 1.289 by root, Tue Mar 16 17:11:49 2010 UTC vs. Revision 1.291 by root, Tue Mar 16 20:32:20 2010 UTC

Diff Legend

Comparing libev/ev.pod (file contents):
Revision 1.289 by root, Tue Mar 16 17:11:49 2010 UTC vs.
Revision 1.291 by root, Tue Mar 16 20:32:20 2010 UTC