… | |
… | |
27 | This module (-family) implements a simple message passing framework. |
27 | This module (-family) implements a simple message passing framework. |
28 | |
28 | |
29 | Despite its simplicity, you can securely message other processes running |
29 | Despite its simplicity, you can securely message other processes running |
30 | on the same or other hosts. |
30 | on the same or other hosts. |
31 | |
31 | |
|
|
32 | At the moment, this module family is severly brokena nd underdocumented, |
|
|
33 | so do not use. This was uploaded mainly to resreve the CPAN namespace - |
|
|
34 | stay tuned! |
|
|
35 | |
32 | =head1 CONCEPTS |
36 | =head1 CONCEPTS |
33 | |
37 | |
34 | =over 4 |
38 | =over 4 |
35 | |
39 | |
36 | =item port |
40 | =item port |
… | |
… | |
68 | |
72 | |
69 | =cut |
73 | =cut |
70 | |
74 | |
71 | package AnyEvent::MP; |
75 | package AnyEvent::MP; |
72 | |
76 | |
73 | use AnyEvent::MP::Util (); |
|
|
74 | use AnyEvent::MP::Node; |
77 | use AnyEvent::MP::Base; |
75 | use AnyEvent::MP::Transport; |
|
|
76 | |
78 | |
77 | use utf8; |
|
|
78 | use common::sense; |
79 | use common::sense; |
79 | |
80 | |
80 | use Carp (); |
81 | use Carp (); |
81 | |
82 | |
82 | use AE (); |
83 | use AE (); |
83 | |
84 | |
84 | use base "Exporter"; |
85 | use base "Exporter"; |
85 | |
86 | |
86 | our $VERSION = '0.0'; |
87 | our $VERSION = '0.02'; |
87 | our @EXPORT = qw(NODE $NODE $PORT snd rcv _any_); |
88 | our @EXPORT = qw( |
88 | |
89 | NODE $NODE $PORT snd rcv _any_ |
89 | our $DEFAULT_SECRET; |
90 | create_port create_port_on |
90 | our $DEFAULT_PORT = "4040"; |
91 | create_miniport |
91 | |
92 | become_slave become_public |
92 | our $CONNECT_INTERVAL = 5; # new connect every 5s, at least |
93 | ); |
93 | our $CONNECT_TIMEOUT = 30; # includes handshake |
|
|
94 | |
|
|
95 | sub default_secret { |
|
|
96 | unless (defined $DEFAULT_SECRET) { |
|
|
97 | if (open my $fh, "<$ENV{HOME}/.aemp-secret") { |
|
|
98 | sysread $fh, $DEFAULT_SECRET, -s $fh; |
|
|
99 | } else { |
|
|
100 | $DEFAULT_SECRET = AnyEvent::MP::Util::nonce 32; |
|
|
101 | } |
|
|
102 | } |
|
|
103 | |
|
|
104 | $DEFAULT_SECRET |
|
|
105 | } |
|
|
106 | |
94 | |
107 | =item NODE / $NODE |
95 | =item NODE / $NODE |
108 | |
96 | |
109 | The C<NODE ()> function and the C<$NODE> variable contain the noderef of |
97 | The C<NODE ()> function and the C<$NODE> variable contain the noderef of |
110 | the local node. The value is initialised by a call to C<become_public> or |
98 | the local node. The value is initialised by a call to C<become_public> or |
111 | C<become_slave>, after which all local port identifiers become invalid. |
99 | C<become_slave>, after which all local port identifiers become invalid. |
112 | |
100 | |
113 | =cut |
|
|
114 | |
|
|
115 | our $UNIQ = sprintf "%x.%x", $$, time; # per-process/node unique cookie |
|
|
116 | our $PUBLIC = 0; |
|
|
117 | our $NODE; |
|
|
118 | our $PORT; |
|
|
119 | |
|
|
120 | our %NODE; # node id to transport mapping, or "undef", for local node |
|
|
121 | our %PORT; # local ports |
|
|
122 | our %LISTENER; # local transports |
|
|
123 | |
|
|
124 | sub NODE() { $NODE } |
|
|
125 | |
|
|
126 | { |
|
|
127 | use POSIX (); |
|
|
128 | my $nodename = (POSIX::uname)[1]; |
|
|
129 | $NODE = "$$\@$nodename"; |
|
|
130 | } |
|
|
131 | |
|
|
132 | sub _ANY_() { 1 } |
|
|
133 | sub _any_() { \&_ANY_ } |
|
|
134 | |
|
|
135 | sub add_node { |
|
|
136 | my ($noderef) = @_; |
|
|
137 | |
|
|
138 | return $NODE{$noderef} |
|
|
139 | if exists $NODE{$noderef}; |
|
|
140 | |
|
|
141 | for (split /,/, $noderef) { |
|
|
142 | return $NODE{$noderef} = $NODE{$_} |
|
|
143 | if exists $NODE{$_}; |
|
|
144 | } |
|
|
145 | |
|
|
146 | # for indirect sends, use a different class |
|
|
147 | my $node = new AnyEvent::MP::Node::Direct $noderef; |
|
|
148 | |
|
|
149 | $NODE{$_} = $node |
|
|
150 | for $noderef, split /,/, $noderef; |
|
|
151 | |
|
|
152 | $node |
|
|
153 | } |
|
|
154 | |
|
|
155 | =item snd $portid, type => @data |
101 | =item snd $portid, type => @data |
156 | |
102 | |
157 | =item snd $portid, @msg |
103 | =item snd $portid, @msg |
158 | |
104 | |
159 | Send the given message to the given port ID, which can identify either a |
105 | Send the given message to the given port ID, which can identify either |
160 | local or a remote port. |
106 | a local or a remote port, and can be either a string or soemthignt hat |
|
|
107 | stringifies a sa port ID (such as a port object :). |
161 | |
108 | |
162 | While the message can be about anything, it is highly recommended to use |
109 | While the message can be about anything, it is highly recommended to use a |
163 | a constant string as first element. |
110 | string as first element (a portid, or some word that indicates a request |
|
|
111 | type etc.). |
164 | |
112 | |
165 | The message data effectively becomes read-only after a call to this |
113 | The message data effectively becomes read-only after a call to this |
166 | function: modifying any argument is not allowed and can cause many |
114 | function: modifying any argument is not allowed and can cause many |
167 | problems. |
115 | problems. |
168 | |
116 | |
… | |
… | |
170 | JSON is used, then only strings, numbers and arrays and hashes consisting |
118 | JSON is used, then only strings, numbers and arrays and hashes consisting |
171 | of those are allowed (no objects). When Storable is used, then anything |
119 | of those are allowed (no objects). When Storable is used, then anything |
172 | that Storable can serialise and deserialise is allowed, and for the local |
120 | that Storable can serialise and deserialise is allowed, and for the local |
173 | node, anything can be passed. |
121 | node, anything can be passed. |
174 | |
122 | |
175 | =cut |
123 | =item $local_port = create_port |
176 | |
124 | |
177 | sub snd(@) { |
125 | Create a new local port object. See the next section for allowed methods. |
178 | my ($noderef, $port) = split /#/, shift, 2; |
|
|
179 | |
126 | |
180 | add_node $noderef |
127 | =cut |
181 | unless exists $NODE{$noderef}; |
|
|
182 | |
128 | |
183 | $NODE{$noderef}->send (["$port", [@_]]); |
129 | sub create_port { |
184 | } |
130 | my $id = "$AnyEvent::MP::Base::UNIQ." . ++$AnyEvent::MP::Base::ID; |
185 | |
131 | |
|
|
132 | my $self = bless { |
|
|
133 | id => "$NODE#$id", |
|
|
134 | names => [$id], |
|
|
135 | }, "AnyEvent::MP::Port"; |
|
|
136 | |
|
|
137 | $AnyEvent::MP::Base::PORT{$id} = sub { |
|
|
138 | unshift @_, $self; |
|
|
139 | |
|
|
140 | for (@{ $self->{rc0}{$_[1]} }) { |
|
|
141 | $_ && &{$_->[0]} |
|
|
142 | && undef $_; |
|
|
143 | } |
|
|
144 | |
|
|
145 | for (@{ $self->{rcv}{$_[1]} }) { |
|
|
146 | $_ && [@_[1 .. @{$_->[1]}]] ~~ $_->[1] |
|
|
147 | && &{$_->[0]} |
|
|
148 | && undef $_; |
|
|
149 | } |
|
|
150 | |
|
|
151 | for (@{ $self->{any} }) { |
|
|
152 | $_ && [@_[0 .. $#{$_->[1]}]] ~~ $_->[1] |
|
|
153 | && &{$_->[0]} |
|
|
154 | && undef $_; |
|
|
155 | } |
|
|
156 | }; |
|
|
157 | |
|
|
158 | $self |
|
|
159 | } |
|
|
160 | |
|
|
161 | =item $portid = miniport { my @msg = @_; $finished } |
|
|
162 | |
|
|
163 | Creates a "mini port", that is, a very lightweight port without any |
|
|
164 | pattern matching behind it, and returns its ID. |
|
|
165 | |
|
|
166 | The block will be called for every message received on the port. When the |
|
|
167 | callback returns a true value its job is considered "done" and the port |
|
|
168 | will be destroyed. Otherwise it will stay alive. |
|
|
169 | |
|
|
170 | The message will be passed as-is, no extra argument (ie.. no port id) will |
|
|
171 | be passed to the callback. |
|
|
172 | |
|
|
173 | If you need the local port id in the callback, this works nicely: |
|
|
174 | |
|
|
175 | my $port; $port = miniport { |
|
|
176 | snd $otherport, reply => $port; |
|
|
177 | }; |
|
|
178 | |
|
|
179 | =cut |
|
|
180 | |
|
|
181 | sub miniport(&) { |
|
|
182 | my $cb = shift; |
|
|
183 | my $id = "$AnyEvent::MP::Base::UNIQ." . ++$AnyEvent::MP::Base::ID; |
|
|
184 | |
|
|
185 | $AnyEvent::MP::Base::PORT{$id} = sub { |
|
|
186 | &$cb |
|
|
187 | and delete $AnyEvent::MP::Base::PORT{$id}; |
|
|
188 | }; |
|
|
189 | |
|
|
190 | "$NODE#$id" |
|
|
191 | } |
|
|
192 | |
|
|
193 | package AnyEvent::MP::Port; |
|
|
194 | |
|
|
195 | =back |
|
|
196 | |
|
|
197 | =head1 METHODS FOR PORT OBJECTS |
|
|
198 | |
|
|
199 | =over 4 |
|
|
200 | |
|
|
201 | =item "$port" |
|
|
202 | |
|
|
203 | A port object stringifies to its port ID, so can be used directly for |
|
|
204 | C<snd> operations. |
|
|
205 | |
|
|
206 | =cut |
|
|
207 | |
|
|
208 | use overload |
|
|
209 | '""' => sub { $_[0]{id} }, |
|
|
210 | fallback => 1; |
|
|
211 | |
186 | =item rcv $portid, type => $callback->(@msg) |
212 | =item $port->rcv (type => $callback->($port, @msg)) |
187 | |
213 | |
188 | =item rcv $portid, $smartmatch => $callback->(@msg) |
214 | =item $port->rcv ($smartmatch => $callback->($port, @msg)) |
189 | |
215 | |
190 | =item rcv $portid, [$smartmatch...] => $callback->(@msg) |
216 | =item $port->rcv ([$smartmatch...] => $callback->($port, @msg)) |
191 | |
217 | |
192 | Register a callback on the port identified by C<$portid>, which I<must> be |
218 | Register a callback on the given port. |
193 | a local port. |
|
|
194 | |
219 | |
195 | The callback has to return a true value when its work is done, after |
220 | The callback has to return a true value when its work is done, after |
196 | which is will be removed, or a false value in which case it will stay |
221 | which is will be removed, or a false value in which case it will stay |
197 | registered. |
222 | registered. |
198 | |
223 | |
… | |
… | |
208 | also the most efficient match (by far). |
233 | also the most efficient match (by far). |
209 | |
234 | |
210 | =cut |
235 | =cut |
211 | |
236 | |
212 | sub rcv($@) { |
237 | sub rcv($@) { |
213 | my ($port, $match, $cb) = @_; |
238 | my ($self, $match, $cb) = @_; |
214 | |
|
|
215 | my $port = $PORT{$port} |
|
|
216 | or do { |
|
|
217 | my ($noderef, $lport) = split /#/, $port; |
|
|
218 | "AnyEvent::MP::Node::Self" eq ref $NODE{$noderef} |
|
|
219 | or Carp::croak "$port: can only rcv on local ports"; |
|
|
220 | |
|
|
221 | $PORT{$lport} |
|
|
222 | or Carp::croak "$port: port does not exist"; |
|
|
223 | |
|
|
224 | $PORT{$port} = $PORT{$lport} # also return |
|
|
225 | }; |
|
|
226 | |
239 | |
227 | if (!ref $match) { |
240 | if (!ref $match) { |
228 | push @{ $port->{rc0}{$match} }, [$cb]; |
241 | push @{ $self->{rc0}{$match} }, [$cb]; |
229 | } elsif (("ARRAY" eq ref $match && !ref $match->[0])) { |
242 | } elsif (("ARRAY" eq ref $match && !ref $match->[0])) { |
230 | my ($type, @match) = @$match; |
243 | my ($type, @match) = @$match; |
231 | @match |
244 | @match |
232 | ? push @{ $port->{rcv}{$match->[0]} }, [$cb, \@match] |
245 | ? push @{ $self->{rcv}{$match->[0]} }, [$cb, \@match] |
233 | : push @{ $port->{rc0}{$match->[0]} }, [$cb]; |
246 | : push @{ $self->{rc0}{$match->[0]} }, [$cb]; |
234 | } else { |
247 | } else { |
235 | push @{ $port->{any} }, [$cb, $match]; |
248 | push @{ $self->{any} }, [$cb, $match]; |
236 | } |
249 | } |
237 | } |
250 | } |
238 | |
251 | |
239 | sub _inject { |
252 | =item $port->register ($name) |
240 | my ($port, $msg) = @{+shift}; |
|
|
241 | |
253 | |
242 | $port = $PORT{$port} |
254 | Registers the given port under the well known name C<$name>. If the name |
243 | or return; |
255 | already exists it is replaced. |
244 | |
256 | |
245 | @_ = @$msg; |
257 | A port can only be registered under one well known name. |
246 | |
258 | |
247 | for (@{ $port->{rc0}{$msg->[0]} }) { |
259 | =cut |
248 | $_ && &{$_->[0]} |
|
|
249 | && undef $_; |
|
|
250 | } |
|
|
251 | |
260 | |
252 | for (@{ $port->{rcv}{$msg->[0]} }) { |
261 | sub register { |
253 | $_ && [@_[1..$#{$_->[1]}]] ~~ $_->[1] |
262 | my ($self, $name) = @_; |
254 | && &{$_->[0]} |
|
|
255 | && undef $_; |
|
|
256 | } |
|
|
257 | |
263 | |
258 | for (@{ $port->{any} }) { |
264 | $self->{wkname} = $name; |
259 | $_ && [@_[0..$#{$_->[1]}]] ~~ $_->[1] |
265 | $AnyEvent::MP::Base::WKP{$name} = "$self"; |
260 | && &{$_->[0]} |
|
|
261 | && undef $_; |
|
|
262 | } |
|
|
263 | } |
266 | } |
264 | |
267 | |
265 | sub normalise_noderef($) { |
268 | =item $port->destroy |
|
|
269 | |
|
|
270 | Explicitly destroy/remove/nuke/vaporise the port. |
|
|
271 | |
|
|
272 | Ports are normally kept alive by there mere existance alone, and need to |
|
|
273 | be destroyed explicitly. |
|
|
274 | |
|
|
275 | =cut |
|
|
276 | |
|
|
277 | sub destroy { |
266 | my ($noderef) = @_; |
278 | my ($self) = @_; |
267 | |
279 | |
268 | my $cv = AE::cv; |
280 | delete $AnyEvent::MP::Base::WKP{ $self->{wkname} }; |
269 | my @res; |
|
|
270 | |
281 | |
271 | $cv->begin (sub { |
282 | delete $AnyEvent::MP::Base::PORT{$_} |
272 | my %seen; |
283 | for @{ $self->{names} }; |
273 | my @refs; |
|
|
274 | for (sort { $a->[0] <=> $b->[0] } @res) { |
|
|
275 | push @refs, $_->[1] unless $seen{$_->[1]}++ |
|
|
276 | } |
|
|
277 | shift->send (join ",", @refs); |
|
|
278 | }); |
|
|
279 | |
|
|
280 | $noderef = $DEFAULT_PORT unless length $noderef; |
|
|
281 | |
|
|
282 | my $idx; |
|
|
283 | for my $t (split /,/, $noderef) { |
|
|
284 | my $pri = ++$idx; |
|
|
285 | |
|
|
286 | #TODO: this should be outside normalise_noderef and in become_public |
|
|
287 | if ($t =~ /^\d*$/) { |
|
|
288 | my $nodename = (POSIX::uname)[1]; |
|
|
289 | |
|
|
290 | $cv->begin; |
|
|
291 | AnyEvent::Socket::resolve_sockaddr $nodename, $t || "aemp=$DEFAULT_PORT", "tcp", 0, undef, sub { |
|
|
292 | for (@_) { |
|
|
293 | my ($service, $host) = AnyEvent::Socket::unpack_sockaddr $_->[3]; |
|
|
294 | push @res, [ |
|
|
295 | $pri += 1e-5, |
|
|
296 | AnyEvent::Socket::format_hostport AnyEvent::Socket::format_address $host, $service |
|
|
297 | ]; |
|
|
298 | } |
|
|
299 | $cv->end; |
|
|
300 | }; |
|
|
301 | |
|
|
302 | # my (undef, undef, undef, undef, @ipv4) = gethostbyname $nodename; |
|
|
303 | # |
|
|
304 | # for (@ipv4) { |
|
|
305 | # push @res, [ |
|
|
306 | # $pri, |
|
|
307 | # AnyEvent::Socket::format_hostport AnyEvent::Socket::format_address $_, $t || $DEFAULT_PORT, |
|
|
308 | # ]; |
|
|
309 | # } |
|
|
310 | } else { |
|
|
311 | my ($host, $port) = AnyEvent::Socket::parse_hostport $t, "aemp=$DEFAULT_PORT" |
|
|
312 | or Carp::croak "$t: unparsable transport descriptor"; |
|
|
313 | |
|
|
314 | $cv->begin; |
|
|
315 | AnyEvent::Socket::resolve_sockaddr $host, $port, "tcp", 0, undef, sub { |
|
|
316 | for (@_) { |
|
|
317 | my ($service, $host) = AnyEvent::Socket::unpack_sockaddr $_->[3]; |
|
|
318 | push @res, [ |
|
|
319 | $pri += 1e-5, |
|
|
320 | AnyEvent::Socket::format_hostport AnyEvent::Socket::format_address $host, $service |
|
|
321 | ]; |
|
|
322 | } |
|
|
323 | $cv->end; |
|
|
324 | } |
|
|
325 | } |
|
|
326 | } |
|
|
327 | |
|
|
328 | $cv->end; |
|
|
329 | |
|
|
330 | $cv |
|
|
331 | } |
284 | } |
332 | |
285 | |
333 | sub become_public { |
286 | =back |
334 | return if $PUBLIC; |
|
|
335 | |
287 | |
336 | my $noderef = join ",", ref $_[0] ? @{+shift} : shift; |
288 | =head1 FUNCTIONS FOR NODES |
337 | my @args = @_; |
|
|
338 | |
289 | |
339 | $NODE = (normalise_noderef $noderef)->recv; |
290 | =over 4 |
340 | |
291 | |
341 | for my $t (split /,/, $NODE) { |
292 | =item mon $noderef, $callback->($noderef, $status, $) |
342 | $NODE{$t} = $NODE{""}; |
|
|
343 | |
293 | |
344 | my ($host, $port) = AnyEvent::Socket::parse_hostport $t; |
294 | Monitors the given noderef. |
345 | |
295 | |
346 | $LISTENER{$t} = AnyEvent::MP::Transport::mp_server $host, $port, |
296 | =item become_public endpoint... |
347 | @args, |
|
|
348 | on_error => sub { |
|
|
349 | die "on_error<@_>\n";#d# |
|
|
350 | }, |
|
|
351 | on_connect => sub { |
|
|
352 | my ($tp) = @_; |
|
|
353 | |
297 | |
354 | $NODE{$tp->{remote_id}} = $_[0]; |
298 | Tells the node to become a public node, i.e. reachable from other nodes. |
355 | }, |
|
|
356 | sub { |
|
|
357 | my ($tp) = @_; |
|
|
358 | |
299 | |
359 | $NODE{"$tp->{peerhost}:$tp->{peerport}"} = $tp; |
300 | If no arguments are given, or the first argument is C<undef>, then |
360 | }, |
301 | AnyEvent::MP tries to bind on port C<4040> on all IP addresses that the |
361 | ; |
302 | local nodename resolves to. |
362 | } |
|
|
363 | |
303 | |
364 | $PUBLIC = 1; |
304 | Otherwise the first argument must be an array-reference with transport |
365 | } |
305 | endpoints ("ip:port", "hostname:port") or port numbers (in which case the |
|
|
306 | local nodename is used as hostname). The endpoints are all resolved and |
|
|
307 | will become the node reference. |
|
|
308 | |
|
|
309 | =cut |
366 | |
310 | |
367 | =back |
311 | =back |
368 | |
312 | |
369 | =head1 NODE MESSAGES |
313 | =head1 NODE MESSAGES |
370 | |
314 | |
… | |
… | |
375 | |
319 | |
376 | =over 4 |
320 | =over 4 |
377 | |
321 | |
378 | =cut |
322 | =cut |
379 | |
323 | |
380 | ############################################################################# |
324 | =item wkp => $name, @reply |
381 | # self node code |
|
|
382 | |
325 | |
383 | sub _new_port($) { |
326 | Replies with the port ID of the specified well-known port, or C<undef>. |
384 | my ($name) = @_; |
|
|
385 | |
327 | |
386 | my ($noderef, $portname) = split /#/, $name; |
328 | =item devnull => ... |
387 | |
329 | |
388 | $PORT{$name} = |
330 | Generic data sink/CPU heat conversion. |
389 | $PORT{$portname} = { |
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390 | names => [$name, $portname], |
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391 | }; |
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392 | } |
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393 | |
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394 | $NODE{""} = new AnyEvent::MP::Node::Self noderef => $NODE; |
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395 | _new_port ""; |
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396 | |
331 | |
397 | =item relay => $port, @msg |
332 | =item relay => $port, @msg |
398 | |
333 | |
399 | Simply forwards the message to the given port. |
334 | Simply forwards the message to the given port. |
400 | |
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401 | =cut |
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402 | |
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403 | rcv "", relay => \&snd; |
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404 | |
335 | |
405 | =item eval => $string[ @reply] |
336 | =item eval => $string[ @reply] |
406 | |
337 | |
407 | Evaluates the given string. If C<@reply> is given, then a message of the |
338 | Evaluates the given string. If C<@reply> is given, then a message of the |
408 | form C<@reply, $@, @evalres> is sent. |
339 | form C<@reply, $@, @evalres> is sent. |
409 | |
340 | |
410 | Example: crash another node. |
341 | Example: crash another node. |
411 | |
342 | |
412 | snd $othernode, eval => "exit"; |
343 | snd $othernode, eval => "exit"; |
413 | |
344 | |
414 | =cut |
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415 | |
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416 | rcv "", eval => sub { |
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417 | my (undef, $string, @reply) = @_; |
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418 | my @res = eval $string; |
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419 | snd @reply, "$@", @res if @reply; |
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420 | }; |
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421 | |
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422 | =item time => @reply |
345 | =item time => @reply |
423 | |
346 | |
424 | Replies the the current node time to C<@reply>. |
347 | Replies the the current node time to C<@reply>. |
425 | |
348 | |
426 | Example: tell the current node to send the current time to C<$myport> in a |
349 | Example: tell the current node to send the current time to C<$myport> in a |
427 | C<timereply> message. |
350 | C<timereply> message. |
428 | |
351 | |
429 | snd $NODE, time => $myport, timereply => 1, 2; |
352 | snd $NODE, time => $myport, timereply => 1, 2; |
430 | # => snd $myport, timereply => 1, 2, <time> |
353 | # => snd $myport, timereply => 1, 2, <time> |
431 | |
354 | |
432 | =cut |
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433 | |
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434 | rcv "", time => sub { shift; snd @_, AE::time }; |
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435 | |
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436 | =back |
355 | =back |
437 | |
356 | |
438 | =head1 SEE ALSO |
357 | =head1 SEE ALSO |
439 | |
358 | |
440 | L<AnyEvent>. |
359 | L<AnyEvent>. |