[ViewVC] Diff of: cvs/AnyEvent-MP/MP.pm

Comparing AnyEvent-MP/MP.pm (file contents):
Revision 1.47 by root, Thu Aug 13 01:57:10 2009 UTC vs.
Revision 1.63 by root, Thu Aug 27 21:29:37 2009 UTC

…		…
9	$NODE # contains this node's noderef	9	$NODE # contains this node's noderef
10	NODE # returns this node's noderef	10	NODE # returns this node's noderef
11	NODE $port # returns the noderef of the port	11	NODE $port # returns the noderef of the port
12		12
13	$SELF # receiving/own port id in rcv callbacks	13	$SELF # receiving/own port id in rcv callbacks
		14
		15	# initialise the node so it can send/receive messages
		16	initialise_node;
14		17
15	# ports are message endpoints	18	# ports are message endpoints
16		19
17	# sending messages	20	# sending messages
18	snd $port, type => data...;	21	snd $port, type => data...;
19	snd $port, @msg;	22	snd $port, @msg;
20	snd @msg_with_first_element_being_a_port;	23	snd @msg_with_first_element_being_a_port;
21		24
22	# miniports	25	# creating/using ports, the simple way
23	my $miniport = port { my @msg = @_; 0 };	26	my $simple_port = port { my @msg = @_; 0 };
24		27
25	# full ports	28	# creating/using ports, tagged message matching
26	my $port = port;	29	my $port = port;
27	rcv $port, smartmatch => $cb->(@msg);
28	rcv $port, ping => sub { snd $_[0], "pong"; 0 };	30	rcv $port, ping => sub { snd $_[0], "pong"; 0 };
29	rcv $port, pong => sub { warn "pong received\n"; 0 };	31	rcv $port, pong => sub { warn "pong received\n"; 0 };
30		32
31	# remote ports	33	# create a port on another node
32	my $port = spawn $node, $initfunc, @initdata;	34	my $port = spawn $node, $initfunc, @initdata;
33
34	# more, smarter, matches (_any_ is exported by this module)
35	rcv $port, [child_died => $pid] => sub { ...
36	rcv $port, [_any_, _any_, 3] => sub { .. $_[2] is 3
37		35
38	# monitoring	36	# monitoring
39	mon $port, $cb->(@msg) # callback is invoked on death	37	mon $port, $cb->(@msg) # callback is invoked on death
40	mon $port, $otherport # kill otherport on abnormal death	38	mon $port, $otherport # kill otherport on abnormal death
41	mon $port, $otherport, @msg # send message on death	39	mon $port, $otherport, @msg # send message on death
…		…
69		67
70	=item port	68	=item port
71		69
72	A port is something you can send messages to (with the C<snd> function).	70	A port is something you can send messages to (with the C<snd> function).
73		71
74	Some ports allow you to register C<rcv> handlers that can match specific	72	Ports allow you to register C<rcv> handlers that can match all or just
75	messages. All C<rcv> handlers will receive messages they match, messages	73	some messages. Messages will not be queued.
76	will not be queued.
77		74
78	=item port id - C<noderef#portname>	75	=item port ID - C<noderef#portname>
79		76
80	A port id is normaly the concatenation of a noderef, a hash-mark (C<#>) as	77	A port ID is the concatenation of a noderef, a hash-mark (C<#>) as
81	separator, and a port name (a printable string of unspecified format). An	78	separator, and a port name (a printable string of unspecified format). An
82	exception is the the node port, whose ID is identical to its node	79	exception is the the node port, whose ID is identical to its node
83	reference.	80	reference.
84		81
85	=item node	82	=item node
86		83
87	A node is a single process containing at least one port - the node	84	A node is a single process containing at least one port - the node port,
88	port. You can send messages to node ports to find existing ports or to	85	which provides nodes to manage each other remotely, and to create new
89	create new ports, among other things.	86	ports.
90		87
91	Nodes are either private (single-process only), slaves (connected to a	88	Nodes are either private (single-process only), slaves (can only talk to
92	master node only) or public nodes (connectable from unrelated nodes).	89	public nodes, but do not need an open port) or public nodes (connectable
		90	from any other node).
93		91
94	=item noderef - C<host:port,host:port...>, C<id@noderef>, C<id>	92	=item node ID - C<[a-za-Z0-9_\-.:]+>
95		93
96	A node reference is a string that either simply identifies the node (for	94	A node ID is a string that either simply identifies the node (for
97	private and slave nodes), or contains a recipe on how to reach a given	95	private and slave nodes), or contains a recipe on how to reach a given
98	node (for public nodes).	96	node (for public nodes).
99		97
100	This recipe is simply a comma-separated list of C<address:port> pairs (for	98	This recipe is simply a comma-separated list of C<address:port> pairs (for
101	TCP/IP, other protocols might look different).	99	TCP/IP, other protocols might look different).
…		…
127	use base "Exporter";	125	use base "Exporter";
128		126
129	our $VERSION = $AnyEvent::MP::Kernel::VERSION;	127	our $VERSION = $AnyEvent::MP::Kernel::VERSION;
130		128
131	our @EXPORT = qw(	129	our @EXPORT = qw(
132	NODE $NODE *SELF node_of _any_	130	NODE $NODE *SELF node_of after
133	resolve_node initialise_node	131	resolve_node initialise_node
134	snd rcv mon kil reg psub spawn	132	snd rcv mon mon_guard kil reg psub spawn
135	port	133	port
136	);	134	);
137		135
138	our $SELF;	136	our $SELF;
139		137
…		…
143	kil $SELF, die => $msg;	141	kil $SELF, die => $msg;
144	}	142	}
145		143
146	=item $thisnode = NODE / $NODE	144	=item $thisnode = NODE / $NODE
147		145
148	The C<NODE> function returns, and the C<$NODE> variable contains	146	The C<NODE> function returns, and the C<$NODE> variable contains the
149	the noderef of the local node. The value is initialised by a call	147	node id of the local node. The value is initialised by a call to
150	to C<become_public> or C<become_slave>, after which all local port	148	C<initialise_node>.
151	identifiers become invalid.
152		149
153	=item $noderef = node_of $port	150	=item $nodeid = node_of $port
154		151
155	Extracts and returns the noderef from a portid or a noderef.	152	Extracts and returns the noderef from a port ID or a node ID.
156		153
157	=item initialise_node $noderef, $seednode, $seednode...	154	=item initialise_node $profile_name
158
159	=item initialise_node "slave/", $master, $master...
160		155
161	Before a node can talk to other nodes on the network it has to initialise	156	Before a node can talk to other nodes on the network it has to initialise
162	itself - the minimum a node needs to know is it's own name, and optionally	157	itself - the minimum a node needs to know is it's own name, and optionally
163	it should know the noderefs of some other nodes in the network.	158	it should know the noderefs of some other nodes in the network.
164		159
165	This function initialises a node - it must be called exactly once (or	160	This function initialises a node - it must be called exactly once (or
166	never) before calling other AnyEvent::MP functions.	161	never) before calling other AnyEvent::MP functions.
167		162
168	All arguments are noderefs, which can be either resolved or unresolved.	163	All arguments (optionally except for the first) are noderefs, which can be
		164	either resolved or unresolved.
		165
		166	The first argument will be looked up in the configuration database first
		167	(if it is C<undef> then the current nodename will be used instead) to find
		168	the relevant configuration profile (see L<aemp>). If none is found then
		169	the default configuration is used. The configuration supplies additional
		170	seed/master nodes and can override the actual noderef.
169		171
170	There are two types of networked nodes, public nodes and slave nodes:	172	There are two types of networked nodes, public nodes and slave nodes:
171		173
172	=over 4	174	=over 4
173		175
174	=item public nodes	176	=item public nodes
175		177
176	For public nodes, C<$noderef> must either be a (possibly unresolved)	178	For public nodes, C<$noderef> (supplied either directly to
177	noderef, in which case it will be resolved, or C<undef> (or missing), in	179	C<initialise_node> or indirectly via a profile or the nodename) must be a
178	which case the noderef will be guessed.	180	noderef (possibly unresolved, in which case it will be resolved).
179		181
180	Afterwards, the node will bind itself on all endpoints and try to connect	182	After resolving, the node will bind itself on all endpoints.
181	to all additional C<$seednodes> that are specified. Seednodes are optional
182	and can be used to quickly bootstrap the node into an existing network.
183		183
184	=item slave nodes	184	=item slave nodes
185		185
186	When the C<$noderef> is the special string C<slave/>, then the node will	186	When the C<$noderef> (either as given or overriden by the config file)
		187	is the special string C<slave/>, then the node will become a slave
187	become a slave node. Slave nodes cannot be contacted from outside and will	188	node. Slave nodes cannot be contacted from outside, and cannot talk to
188	route most of their traffic to the master node that they attach to.	189	each other (at least in this version of AnyEvent::MP).
189		190
190	At least one additional noderef is required: The node will try to connect	191	Slave nodes work by creating connections to all public nodes, using the
191	to all of them and will become a slave attached to the first node it can	192	L<AnyEvent::MP::Global> service.
192	successfully connect to.
193		193
194	=back	194	=back
195		195
196	This function will block until all nodes have been resolved and, for slave	196	After initialising itself, the node will connect to all additional
197	nodes, until it has successfully established a connection to a master	197	C<$seednodes> that are specified diretcly or via a profile. Seednodes are
198	server.	198	optional and can be used to quickly bootstrap the node into an existing
		199	network.
199		200
		201	All the seednodes will also be specially marked to automatically retry
		202	connecting to them indefinitely, so make sure that seednodes are really
		203	reliable and up (this might also change in the future).
		204
200	Example: become a public node listening on the default node.	205	Example: become a public node listening on the guessed noderef, or the one
		206	specified via C<aemp> for the current node. This should be the most common
		207	form of invocation for "daemon"-type nodes.
201		208
202	initialise_node;	209	initialise_node;
		210
		211	Example: become a slave node to any of the the seednodes specified via
		212	C<aemp>. This form is often used for commandline clients.
		213
		214	initialise_node "slave/";
203		215
204	Example: become a public node, and try to contact some well-known master	216	Example: become a public node, and try to contact some well-known master
205	servers to become part of the network.	217	servers to become part of the network.
206		218
207	initialise_node undef, "master1", "master2";	219	initialise_node undef, "master1", "master2";
…		…
210		222
211	initialise_node 4041;	223	initialise_node 4041;
212		224
213	Example: become a public node, only visible on localhost port 4044.	225	Example: become a public node, only visible on localhost port 4044.
214		226
215	initialise_node "locahost:4044";	227	initialise_node "localhost:4044";
216
217	Example: become a slave node to any of the specified master servers.
218
219	initialise_node "slave/", "master1", "192.168.13.17", "mp.example.net";
220		228
221	=item $cv = resolve_node $noderef	229	=item $cv = resolve_node $noderef
222		230
223	Takes an unresolved node reference that may contain hostnames and	231	Takes an unresolved node reference that may contain hostnames and
224	abbreviated IDs, resolves all of them and returns a resolved node	232	abbreviated IDs, resolves all of them and returns a resolved node
…		…
261	=item snd $port, type => @data	269	=item snd $port, type => @data
262		270
263	=item snd $port, @msg	271	=item snd $port, @msg
264		272
265	Send the given message to the given port ID, which can identify either	273	Send the given message to the given port ID, which can identify either
266	a local or a remote port, and can be either a string or soemthignt hat	274	a local or a remote port, and must be a port ID.
267	stringifies a sa port ID (such as a port object :).
268		275
269	While the message can be about anything, it is highly recommended to use a	276	While the message can be about anything, it is highly recommended to use a
270	string as first element (a portid, or some word that indicates a request	277	string as first element (a port ID, or some word that indicates a request
271	type etc.).	278	type etc.).
272		279
273	The message data effectively becomes read-only after a call to this	280	The message data effectively becomes read-only after a call to this
274	function: modifying any argument is not allowed and can cause many	281	function: modifying any argument is not allowed and can cause many
275	problems.	282	problems.
…		…
280	that Storable can serialise and deserialise is allowed, and for the local	287	that Storable can serialise and deserialise is allowed, and for the local
281	node, anything can be passed.	288	node, anything can be passed.
282		289
283	=item $local_port = port	290	=item $local_port = port
284		291
285	Create a new local port object that can be used either as a pattern	292	Create a new local port object and returns its port ID. Initially it has
286	matching port ("full port") or a single-callback port ("miniport"),	293	no callbacks set and will throw an error when it receives messages.
287	depending on how C<rcv> callbacks are bound to the object.
288		294
289	=item $port = port { my @msg = @_; $finished }	295	=item $local_port = port { my @msg = @_ }
290		296
291	Creates a "miniport", that is, a very lightweight port without any pattern	297	Creates a new local port, and returns its ID. Semantically the same as
292	matching behind it, and returns its ID. Semantically the same as creating
293	a port and calling C<rcv $port, $callback> on it.	298	creating a port and calling C<rcv $port, $callback> on it.
294		299
295	The block will be called for every message received on the port. When the	300	The block will be called for every message received on the port, with the
296	callback returns a true value its job is considered "done" and the port	301	global variable C<$SELF> set to the port ID. Runtime errors will cause the
297	will be destroyed. Otherwise it will stay alive.	302	port to be C<kil>ed. The message will be passed as-is, no extra argument
		303	(i.e. no port ID) will be passed to the callback.
298		304
299	The message will be passed as-is, no extra argument (i.e. no port id) will	305	If you want to stop/destroy the port, simply C<kil> it:
300	be passed to the callback.
301		306
302	If you need the local port id in the callback, this works nicely:	307	my $port = port {
303		308	my @msg = @_;
304	my $port; $port = port {	309	...
305	snd $otherport, reply => $port;	310	kil $SELF;
306	};	311	};
307		312
308	=cut	313	=cut
309		314
310	sub rcv($@);	315	sub rcv($@);
		316
		317	sub _kilme {
		318	die "received message on port without callback";
		319	}
311		320
312	sub port(;&) {	321	sub port(;&) {
313	my $id = "$UNIQ." . $ID++;	322	my $id = "$UNIQ." . $ID++;
314	my $port = "$NODE#$id";	323	my $port = "$NODE#$id";
315		324
316	if (@_) {	325	rcv $port, shift \|\| \&_kilme;
317	rcv $port, shift;
318	} else {
319	$PORT{$id} = sub { }; # nop
320	}
321		326
322	$port	327	$port
323	}	328	}
324		329
325	=item reg $port, $name
326
327	=item reg $name
328
329	Registers the given port (or C<$SELF><<< if missing) under the name
330	C<$name>. If the name already exists it is replaced.
331
332	A port can only be registered under one well known name.
333
334	A port automatically becomes unregistered when it is killed.
335
336	=cut
337
338	sub reg(@) {
339	my $port = @_ > 1 ? shift : $SELF \|\| Carp::croak 'reg: called with one argument only, but $SELF not set,';
340
341	$REG{$_[0]} = $port;
342	}
343
344	=item rcv $port, $callback->(@msg)	330	=item rcv $local_port, $callback->(@msg)
345		331
346	Replaces the callback on the specified miniport (after converting it to	332	Replaces the default callback on the specified port. There is no way to
347	one if required).	333	remove the default callback: use C<sub { }> to disable it, or better
348		334	C<kil> the port when it is no longer needed.
349	=item rcv $port, tagstring => $callback->(@msg), ...
350
351	=item rcv $port, $smartmatch => $callback->(@msg), ...
352
353	=item rcv $port, [$smartmatch...] => $callback->(@msg), ...
354
355	Register callbacks to be called on matching messages on the given full
356	port (after converting it to one if required) and return the port.
357
358	The callback has to return a true value when its work is done, after
359	which is will be removed, or a false value in which case it will stay
360	registered.
361		335
362	The global C<$SELF> (exported by this module) contains C<$port> while	336	The global C<$SELF> (exported by this module) contains C<$port> while
363	executing the callback.	337	executing the callback. Runtime errors during callback execution will
		338	result in the port being C<kil>ed.
364		339
365	Runtime errors during callback execution will result in the port being	340	The default callback received all messages not matched by a more specific
366	C<kil>ed.	341	C<tag> match.
367		342
368	If the match is an array reference, then it will be matched against the	343	=item rcv $local_port, tag => $callback->(@msg_without_tag), ...
369	first elements of the message, otherwise only the first element is being
370	matched.
371		344
372	Any element in the match that is specified as C<_any_> (a function	345	Register (or replace) callbacks to be called on messages starting with the
373	exported by this module) matches any single element of the message.	346	given tag on the given port (and return the port), or unregister it (when
		347	C<$callback> is C<$undef> or missing). There can only be one callback
		348	registered for each tag.
374		349
375	While not required, it is highly recommended that the first matching	350	The original message will be passed to the callback, after the first
376	element is a string identifying the message. The one-string-only match is	351	element (the tag) has been removed. The callback will use the same
377	also the most efficient match (by far).	352	environment as the default callback (see above).
378		353
379	Example: create a port and bind receivers on it in one go.	354	Example: create a port and bind receivers on it in one go.
380		355
381	my $port = rcv port,	356	my $port = rcv port,
382	msg1 => sub { ...; 0 },	357	msg1 => sub { ... },
383	msg2 => sub { ...; 0 },	358	msg2 => sub { ... },
384	;	359	;
385		360
386	Example: create a port, bind receivers and send it in a message elsewhere	361	Example: create a port, bind receivers and send it in a message elsewhere
387	in one go:	362	in one go:
388		363
389	snd $otherport, reply =>	364	snd $otherport, reply =>
390	rcv port,	365	rcv port,
391	msg1 => sub { ...; 0 },	366	msg1 => sub { ... },
392	...	367	...
393	;	368	;
		369
		370	Example: temporarily register a rcv callback for a tag matching some port
		371	(e.g. for a rpc reply) and unregister it after a message was received.
		372
		373	rcv $port, $otherport => sub {
		374	my @reply = @_;
		375
		376	rcv $SELF, $otherport;
		377	};
394		378
395	=cut	379	=cut
396		380
397	sub rcv($@) {	381	sub rcv($@) {
398	my $port = shift;	382	my $port = shift;
399	my ($noderef, $portid) = split /#/, $port, 2;	383	my ($noderef, $portid) = split /#/, $port, 2;
400		384
401	($NODE{$noderef} \|\| add_node $noderef) == $NODE{""}	385	$NODE{$noderef} == $NODE{""}
402	or Carp::croak "$port: rcv can only be called on local ports, caught";	386	or Carp::croak "$port: rcv can only be called on local ports, caught";
403		387
404	if (@_ == 1) {	388	while (@_) {
		389	if (ref $_[0]) {
		390	if (my $self = $PORT_DATA{$portid}) {
		391	"AnyEvent::MP::Port" eq ref $self
		392	or Carp::croak "$port: rcv can only be called on message matching ports, caught";
		393
		394	$self->[2] = shift;
		395	} else {
405	my $cb = shift;	396	my $cb = shift;
406	delete $PORT_DATA{$portid};
407	$PORT{$portid} = sub {	397	$PORT{$portid} = sub {
408	local $SELF = $port;	398	local $SELF = $port;
409	eval {	399	eval { &$cb }; _self_die if $@;
410	&$cb	400	};
411	and kil $port;
412	};	401	}
413	_self_die if $@;	402	} elsif (defined $_[0]) {
414	};
415	} else {
416	my $self = $PORT_DATA{$portid} \|\|= do {	403	my $self = $PORT_DATA{$portid} \|\|= do {
417	my $self = bless {	404	my $self = bless [$PORT{$port} \|\| sub { }, { }, $port], "AnyEvent::MP::Port";
418	id => $port,
419	}, "AnyEvent::MP::Port";
420		405
421	$PORT{$portid} = sub {	406	$PORT{$portid} = sub {
422	local $SELF = $port;	407	local $SELF = $port;
423		408
424	eval {
425	for (@{ $self->{rc0}{$_[0]} }) {	409	if (my $cb = $self->[1]{$_[0]}) {
426	$_ && &{$_->[0]}	410	shift;
427	&& undef $_;	411	eval { &$cb }; _self_die if $@;
428	}	412	} else {
429
430	for (@{ $self->{rcv}{$_[0]} }) {
431	$_ && [@_[1 .. @{$_->[1]}]] ~~ $_->[1]
432	&& &{$_->[0]}	413	&{ $self->[0] };
433	&& undef $_;
434	}
435
436	for (@{ $self->{any} }) {
437	$_ && [@_[0 .. $#{$_->[1]}]] ~~ $_->[1]
438	&& &{$_->[0]}
439	&& undef $_;
440	}	414	}
441	};	415	};
442	_self_die if $@;	416
		417	$self
443	};	418	};
444		419
445	$self
446	};
447
448	"AnyEvent::MP::Port" eq ref $self	420	"AnyEvent::MP::Port" eq ref $self
449	or Carp::croak "$port: rcv can only be called on message matching ports, caught";	421	or Carp::croak "$port: rcv can only be called on message matching ports, caught";
450		422
451	while (@_) {
452	my ($match, $cb) = splice @_, 0, 2;	423	my ($tag, $cb) = splice @_, 0, 2;
453		424
454	if (!ref $match) {	425	if (defined $cb) {
455	push @{ $self->{rc0}{$match} }, [$cb];	426	$self->[1]{$tag} = $cb;
456	} elsif (("ARRAY" eq ref $match && !ref $match->[0])) {
457	my ($type, @match) = @$match;
458	@match
459	? push @{ $self->{rcv}{$match->[0]} }, [$cb, \@match]
460	: push @{ $self->{rc0}{$match->[0]} }, [$cb];
461	} else {	427	} else {
462	push @{ $self->{any} }, [$cb, $match];	428	delete $self->[1]{$tag};
463	}	429	}
464	}	430	}
465	}	431	}
466		432
467	$port	433	$port
…		…
522	will arrive, or the monitoring action will be invoked after possible	488	will arrive, or the monitoring action will be invoked after possible
523	message loss has been detected. No messages will be lost "in between"	489	message loss has been detected. No messages will be lost "in between"
524	(after the first lost message no further messages will be received by the	490	(after the first lost message no further messages will be received by the
525	port). After the monitoring action was invoked, further messages might get	491	port). After the monitoring action was invoked, further messages might get
526	delivered again.	492	delivered again.
		493
		494	Note that monitoring-actions are one-shot: once released, they are removed
		495	and will not trigger again.
527		496
528	In the first form (callback), the callback is simply called with any	497	In the first form (callback), the callback is simply called with any
529	number of C<@reason> elements (no @reason means that the port was deleted	498	number of C<@reason> elements (no @reason means that the port was deleted
530	"normally"). Note also that I<< the callback B<must> never die >>, so use	499	"normally"). Note also that I<< the callback B<must> never die >>, so use
531	C<eval> if unsure.	500	C<eval> if unsure.
…		…
692	my $id = "$RUNIQ." . $ID++;	661	my $id = "$RUNIQ." . $ID++;
693		662
694	$_[0] =~ /::/	663	$_[0] =~ /::/
695	or Carp::croak "spawn init function must be a fully-qualified name, caught";	664	or Carp::croak "spawn init function must be a fully-qualified name, caught";
696		665
697	($NODE{$noderef} \|\| add_node $noderef)	666	snd_to_func $noderef, "AnyEvent::MP::_spawn" => $id, @_;
698	->send (["", "AnyEvent::MP::_spawn" => $id, @_]);
699		667
700	"$noderef#$id"	668	"$noderef#$id"
701	}	669	}
702		670
703	=back	671	=item after $timeout, @msg
704		672
705	=head1 NODE MESSAGES	673	=item after $timeout, $callback
706		674
707	Nodes understand the following messages sent to them. Many of them take	675	Either sends the given message, or call the given callback, after the
708	arguments called C<@reply>, which will simply be used to compose a reply	676	specified number of seconds.
709	message - C<$reply[0]> is the port to reply to, C<$reply[1]> the type and
710	the remaining arguments are simply the message data.
711		677
712	While other messages exist, they are not public and subject to change.	678	This is simply a utility function that come sin handy at times.
713		679
714	=over 4
715
716	=cut	680	=cut
717		681
718	=item lookup => $name, @reply	682	sub after($@) {
		683	my ($timeout, @action) = @_;
719		684
720	Replies with the port ID of the specified well-known port, or C<undef>.	685	my $t; $t = AE::timer $timeout, 0, sub {
721		686	undef $t;
722	=item devnull => ...	687	ref $action[0]
723		688	? $action[0]()
724	Generic data sink/CPU heat conversion.	689	: snd @action;
725		690	};
726	=item relay => $port, @msg	691	}
727
728	Simply forwards the message to the given port.
729
730	=item eval => $string[ @reply]
731
732	Evaluates the given string. If C<@reply> is given, then a message of the
733	form C<@reply, $@, @evalres> is sent.
734
735	Example: crash another node.
736
737	snd $othernode, eval => "exit";
738
739	=item time => @reply
740
741	Replies the the current node time to C<@reply>.
742
743	Example: tell the current node to send the current time to C<$myport> in a
744	C<timereply> message.
745
746	snd $NODE, time => $myport, timereply => 1, 2;
747	# => snd $myport, timereply => 1, 2, <time>
748		692
749	=back	693	=back
750		694
751	=head1 AnyEvent::MP vs. Distributed Erlang	695	=head1 AnyEvent::MP vs. Distributed Erlang
752		696
…		…
771	convenience functionality.	715	convenience functionality.
772		716
773	This means that AEMP requires a less tightly controlled environment at the	717	This means that AEMP requires a less tightly controlled environment at the
774	cost of longer node references and a slightly higher management overhead.	718	cost of longer node references and a slightly higher management overhead.
775		719
		720	=item * Erlang has a "remote ports are like local ports" philosophy, AEMP
		721	uses "local ports are like remote ports".
		722
		723	The failure modes for local ports are quite different (runtime errors
		724	only) then for remote ports - when a local port dies, you I<know> it dies,
		725	when a connection to another node dies, you know nothing about the other
		726	port.
		727
		728	Erlang pretends remote ports are as reliable as local ports, even when
		729	they are not.
		730
		731	AEMP encourages a "treat remote ports differently" philosophy, with local
		732	ports being the special case/exception, where transport errors cannot
		733	occur.
		734
776	=item * Erlang uses processes and a mailbox, AEMP does not queue.	735	=item * Erlang uses processes and a mailbox, AEMP does not queue.
777		736
778	Erlang uses processes that selctively receive messages, and therefore	737	Erlang uses processes that selectively receive messages, and therefore
779	needs a queue. AEMP is event based, queuing messages would serve no useful	738	needs a queue. AEMP is event based, queuing messages would serve no
780	purpose.	739	useful purpose. For the same reason the pattern-matching abilities of
		740	AnyEvent::MP are more limited, as there is little need to be able to
		741	filter messages without dequeing them.
781		742
782	(But see L<Coro::MP> for a more Erlang-like process model on top of AEMP).	743	(But see L<Coro::MP> for a more Erlang-like process model on top of AEMP).
783		744
784	=item * Erlang sends are synchronous, AEMP sends are asynchronous.	745	=item * Erlang sends are synchronous, AEMP sends are asynchronous.
785		746
786	Sending messages in Erlang is synchronous and blocks the process. AEMP	747	Sending messages in Erlang is synchronous and blocks the process (and
787	sends are immediate, connection establishment is handled in the	748	so does not need a queue that can overflow). AEMP sends are immediate,
788	background.	749	connection establishment is handled in the background.
789		750
790	=item * Erlang can silently lose messages, AEMP cannot.	751	=item * Erlang suffers from silent message loss, AEMP does not.
791		752
792	Erlang makes few guarantees on messages delivery - messages can get lost	753	Erlang makes few guarantees on messages delivery - messages can get lost
793	without any of the processes realising it (i.e. you send messages a, b,	754	without any of the processes realising it (i.e. you send messages a, b,
794	and c, and the other side only receives messages a and c).	755	and c, and the other side only receives messages a and c).
795		756
…		…
807	eventually be killed - it cannot happen that a node detects a port as dead	768	eventually be killed - it cannot happen that a node detects a port as dead
808	and then later sends messages to it, finding it is still alive.	769	and then later sends messages to it, finding it is still alive.
809		770
810	=item * Erlang can send messages to the wrong port, AEMP does not.	771	=item * Erlang can send messages to the wrong port, AEMP does not.
811		772
812	In Erlang it is quite possible that a node that restarts reuses a process	773	In Erlang it is quite likely that a node that restarts reuses a process ID
813	ID known to other nodes for a completely different process, causing	774	known to other nodes for a completely different process, causing messages
814	messages destined for that process to end up in an unrelated process.	775	destined for that process to end up in an unrelated process.
815		776
816	AEMP never reuses port IDs, so old messages or old port IDs floating	777	AEMP never reuses port IDs, so old messages or old port IDs floating
817	around in the network will not be sent to an unrelated port.	778	around in the network will not be sent to an unrelated port.
818		779
819	=item * Erlang uses unprotected connections, AEMP uses secure	780	=item * Erlang uses unprotected connections, AEMP uses secure

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Comparing AnyEvent-MP/MP.pm (file contents): Revision 1.47 by root, Thu Aug 13 01:57:10 2009 UTC vs. Revision 1.63 by root, Thu Aug 27 21:29:37 2009 UTC

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Comparing AnyEvent-MP/MP.pm (file contents):
Revision 1.47 by root, Thu Aug 13 01:57:10 2009 UTC vs.
Revision 1.63 by root, Thu Aug 27 21:29:37 2009 UTC