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Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.97 by root, Thu Oct 2 11:07:59 2008 UTC vs.
Revision 1.109 by root, Wed Jan 14 02:03:43 2009 UTC

14 14
15AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent 15AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent
16 16
17=cut 17=cut
18 18
19our $VERSION = 4.3; 19our $VERSION = 4.331;
20 20
21=head1 SYNOPSIS 21=head1 SYNOPSIS
22 22
23 use AnyEvent; 23 use AnyEvent;
24 use AnyEvent::Handle; 24 use AnyEvent::Handle;
27 27
28 my $handle = 28 my $handle =
29 AnyEvent::Handle->new ( 29 AnyEvent::Handle->new (
30 fh => \*STDIN, 30 fh => \*STDIN,
31 on_eof => sub { 31 on_eof => sub {
32 $cv->broadcast; 32 $cv->send;
33 }, 33 },
34 ); 34 );
35 35
36 # send some request line 36 # send some request line
37 $handle->push_write ("getinfo\015\012"); 37 $handle->push_write ("getinfo\015\012");
59treatment of characters applies to this module as well. 59treatment of characters applies to this module as well.
60 60
61All callbacks will be invoked with the handle object as their first 61All callbacks will be invoked with the handle object as their first
62argument. 62argument.
63 63
64=head2 SIGPIPE is not handled by this module
65
66SIGPIPE is not handled by this module, so one of the practical
67requirements of using it is to ignore SIGPIPE (C<$SIG{PIPE} =
68'IGNORE'>). At least, this is highly recommend in a networked program: If
69you use AnyEvent::Handle in a filter program (like sort), exiting on
70SIGPIPE is probably the right thing to do.
71
72=head1 METHODS 64=head1 METHODS
73 65
74=over 4 66=over 4
75 67
76=item B<new (%args)> 68=item B<new (%args)>
92Set the callback to be called when an end-of-file condition is detected, 84Set the callback to be called when an end-of-file condition is detected,
93i.e. in the case of a socket, when the other side has closed the 85i.e. in the case of a socket, when the other side has closed the
94connection cleanly. 86connection cleanly.
95 87
96For sockets, this just means that the other side has stopped sending data, 88For sockets, this just means that the other side has stopped sending data,
97you can still try to write data, and, in fact, one can return from the eof 89you can still try to write data, and, in fact, one can return from the EOF
98callback and continue writing data, as only the read part has been shut 90callback and continue writing data, as only the read part has been shut
99down. 91down.
100 92
101While not mandatory, it is I<highly> recommended to set an eof callback, 93While not mandatory, it is I<highly> recommended to set an EOF callback,
102otherwise you might end up with a closed socket while you are still 94otherwise you might end up with a closed socket while you are still
103waiting for data. 95waiting for data.
104 96
105If an EOF condition has been detected but no C<on_eof> callback has been 97If an EOF condition has been detected but no C<on_eof> callback has been
106set, then a fatal error will be raised with C<$!> set to <0>. 98set, then a fatal error will be raised with C<$!> set to <0>.
263You can also provide your own TLS connection object, but you have 255You can also provide your own TLS connection object, but you have
264to make sure that you call either C<Net::SSLeay::set_connect_state> 256to make sure that you call either C<Net::SSLeay::set_connect_state>
265or C<Net::SSLeay::set_accept_state> on it before you pass it to 257or C<Net::SSLeay::set_accept_state> on it before you pass it to
266AnyEvent::Handle. 258AnyEvent::Handle.
267 259
260B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
261passing in the wrong integer will lead to certain crash. This most often
262happens when one uses a stylish C<< tls => 1 >> and is surprised about the
263segmentation fault.
264
268See the C<< ->starttls >> method for when need to start TLS negotiation later. 265See the C<< ->starttls >> method for when need to start TLS negotiation later.
269 266
270=item tls_ctx => $ssl_ctx 267=item tls_ctx => $ssl_ctx
271 268
272Use the given C<Net::SSLeay::CTX> object to create the new TLS connection 269Use the given C<Net::SSLeay::CTX> object to create the new TLS connection
334 331
335 $! = $errno; 332 $! = $errno;
336 333
337 if ($self->{on_error}) { 334 if ($self->{on_error}) {
338 $self->{on_error}($self, $fatal); 335 $self->{on_error}($self, $fatal);
339 } else { 336 } elsif ($self->{fh}) {
340 Carp::croak "AnyEvent::Handle uncaught error: $!"; 337 Carp::croak "AnyEvent::Handle uncaught error: $!";
341 } 338 }
342} 339}
343 340
344=item $fh = $handle->fh 341=item $fh = $handle->fh
382} 379}
383 380
384=item $handle->autocork ($boolean) 381=item $handle->autocork ($boolean)
385 382
386Enables or disables the current autocork behaviour (see C<autocork> 383Enables or disables the current autocork behaviour (see C<autocork>
387constructor argument). 384constructor argument). Changes will only take effect on the next write.
388 385
389=cut 386=cut
387
388sub autocork {
389 $_[0]{autocork} = $_[1];
390}
390 391
391=item $handle->no_delay ($boolean) 392=item $handle->no_delay ($boolean)
392 393
393Enables or disables the C<no_delay> setting (see constructor argument of 394Enables or disables the C<no_delay> setting (see constructor argument of
394the same name for details). 395the same name for details).
1379sub starttls { 1380sub starttls {
1380 my ($self, $ssl, $ctx) = @_; 1381 my ($self, $ssl, $ctx) = @_;
1381 1382
1382 require Net::SSLeay; 1383 require Net::SSLeay;
1383 1384
1384 Carp::croak "it is an error to call starttls more than once on an Anyevent::Handle object" 1385 Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
1385 if $self->{tls}; 1386 if $self->{tls};
1386 1387
1387 if ($ssl eq "accept") { 1388 if ($ssl eq "accept") {
1388 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1389 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
1389 Net::SSLeay::set_accept_state ($ssl); 1390 Net::SSLeay::set_accept_state ($ssl);
1478 @linger = (); 1479 @linger = ();
1479 }); 1480 });
1480 } 1481 }
1481} 1482}
1482 1483
1484=item $handle->destroy
1485
1486Shuts down the handle object as much as possible - this call ensures that
1487no further callbacks will be invoked and resources will be freed as much
1488as possible. You must not call any methods on the object afterwards.
1489
1490Normally, you can just "forget" any references to an AnyEvent::Handle
1491object and it will simply shut down. This works in fatal error and EOF
1492callbacks, as well as code outside. It does I<NOT> work in a read or write
1493callback, so when you want to destroy the AnyEvent::Handle object from
1494within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
1495that case.
1496
1497The handle might still linger in the background and write out remaining
1498data, as specified by the C<linger> option, however.
1499
1500=cut
1501
1502sub destroy {
1503 my ($self) = @_;
1504
1505 $self->DESTROY;
1506 %$self = ();
1507}
1508
1483=item AnyEvent::Handle::TLS_CTX 1509=item AnyEvent::Handle::TLS_CTX
1484 1510
1485This function creates and returns the Net::SSLeay::CTX object used by 1511This function creates and returns the Net::SSLeay::CTX object used by
1486default for TLS mode. 1512default for TLS mode.
1487 1513
1519 1545
1520 1546
1521=head1 NONFREQUENTLY ASKED QUESTIONS 1547=head1 NONFREQUENTLY ASKED QUESTIONS
1522 1548
1523=over 4 1549=over 4
1550
1551=item I C<undef> the AnyEvent::Handle reference inside my callback and
1552still get further invocations!
1553
1554That's because AnyEvent::Handle keeps a reference to itself when handling
1555read or write callbacks.
1556
1557It is only safe to "forget" the reference inside EOF or error callbacks,
1558from within all other callbacks, you need to explicitly call the C<<
1559->destroy >> method.
1560
1561=item I get different callback invocations in TLS mode/Why can't I pause
1562reading?
1563
1564Unlike, say, TCP, TLS connections do not consist of two independent
1565communication channels, one for each direction. Or put differently. The
1566read and write directions are not independent of each other: you cannot
1567write data unless you are also prepared to read, and vice versa.
1568
1569This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>
1570callback invocations when you are not expecting any read data - the reason
1571is that AnyEvent::Handle always reads in TLS mode.
1572
1573During the connection, you have to make sure that you always have a
1574non-empty read-queue, or an C<on_read> watcher. At the end of the
1575connection (or when you no longer want to use it) you can call the
1576C<destroy> method.
1524 1577
1525=item How do I read data until the other side closes the connection? 1578=item How do I read data until the other side closes the connection?
1526 1579
1527If you just want to read your data into a perl scalar, the easiest way 1580If you just want to read your data into a perl scalar, the easiest way
1528to achieve this is by setting an C<on_read> callback that does nothing, 1581to achieve this is by setting an C<on_read> callback that does nothing,
1538 1591
1539The reason to use C<on_error> is that TCP connections, due to latencies 1592The reason to use C<on_error> is that TCP connections, due to latencies
1540and packets loss, might get closed quite violently with an error, when in 1593and packets loss, might get closed quite violently with an error, when in
1541fact, all data has been received. 1594fact, all data has been received.
1542 1595
1543It is usually better to use acknowledgements when transfering data, 1596It is usually better to use acknowledgements when transferring data,
1544to make sure the other side hasn't just died and you got the data 1597to make sure the other side hasn't just died and you got the data
1545intact. This is also one reason why so many internet protocols have an 1598intact. This is also one reason why so many internet protocols have an
1546explicit QUIT command. 1599explicit QUIT command.
1547
1548 1600
1549=item I don't want to destroy the handle too early - how do I wait until 1601=item I don't want to destroy the handle too early - how do I wait until
1550all data has been written? 1602all data has been written?
1551 1603
1552After writing your last bits of data, set the C<on_drain> callback 1604After writing your last bits of data, set the C<on_drain> callback

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