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Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.68 by root, Fri Jun 6 15:35:30 2008 UTC vs.
Revision 1.69 by root, Sun Jun 15 21:44:56 2008 UTC

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124This sets the callback that is called when the write buffer becomes empty 124This sets the callback that is called when the write buffer becomes empty
125(or when the callback is set and the buffer is empty already). 125(or when the callback is set and the buffer is empty already).
126 126
127To append to the write buffer, use the C<< ->push_write >> method. 127To append to the write buffer, use the C<< ->push_write >> method.
128 128
129This callback is useful when you don't want to put all of your write data
130into the queue at once, for example, when you want to write the contents
131of some file to the socket you might not want to read the whole file into
132memory and push it into the queue, but instead only read more data from
133the file when the write queue becomes empty.
134
129=item timeout => $fractional_seconds 135=item timeout => $fractional_seconds
130 136
131If non-zero, then this enables an "inactivity" timeout: whenever this many 137If non-zero, then this enables an "inactivity" timeout: whenever this many
132seconds pass without a successful read or write on the underlying file 138seconds pass without a successful read or write on the underlying file
133handle, the C<on_timeout> callback will be invoked (and if that one is 139handle, the C<on_timeout> callback will be invoked (and if that one is
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593ways, the "simple" way, using only C<on_read> and the "complex" way, using 599ways, the "simple" way, using only C<on_read> and the "complex" way, using
594a queue. 600a queue.
595 601
596In the simple case, you just install an C<on_read> callback and whenever 602In the simple case, you just install an C<on_read> callback and whenever
597new data arrives, it will be called. You can then remove some data (if 603new data arrives, it will be called. You can then remove some data (if
598enough is there) from the read buffer (C<< $handle->rbuf >>) if you want 604enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna
599or not. 605leave the data there if you want to accumulate more (e.g. when only a
606partial message has been received so far).
600 607
601In the more complex case, you want to queue multiple callbacks. In this 608In the more complex case, you want to queue multiple callbacks. In this
602case, AnyEvent::Handle will call the first queued callback each time new 609case, AnyEvent::Handle will call the first queued callback each time new
603data arrives (also the first time it is queued) and removes it when it has 610data arrives (also the first time it is queued) and removes it when it has
604done its job (see C<push_read>, below). 611done its job (see C<push_read>, below).
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622 # handle xml 629 # handle xml
623 }); 630 });
624 }); 631 });
625 }); 632 });
626 633
627Example 2: Implement a client for a protocol that replies either with 634Example 2: Implement a client for a protocol that replies either with "OK"
628"OK" and another line or "ERROR" for one request, and 64 bytes for the 635and another line or "ERROR" for the first request that is sent, and 64
629second request. Due tot he availability of a full queue, we can just 636bytes for the second request. Due to the availability of a queue, we can
630pipeline sending both requests and manipulate the queue as necessary in 637just pipeline sending both requests and manipulate the queue as necessary
631the callbacks: 638in the callbacks.
632 639
633 # request one 640When the first callback is called and sees an "OK" response, it will
641C<unshift> another line-read. This line-read will be queued I<before> the
64264-byte chunk callback.
643
644 # request one, returns either "OK + extra line" or "ERROR"
634 $handle->push_write ("request 1\015\012"); 645 $handle->push_write ("request 1\015\012");
635 646
636 # we expect "ERROR" or "OK" as response, so push a line read 647 # we expect "ERROR" or "OK" as response, so push a line read
637 $handle->push_read (line => sub { 648 $handle->push_read (line => sub {
638 # if we got an "OK", we have to _prepend_ another line, 649 # if we got an "OK", we have to _prepend_ another line,
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645 ... 656 ...
646 }); 657 });
647 } 658 }
648 }); 659 });
649 660
650 # request two 661 # request two, simply returns 64 octets
651 $handle->push_write ("request 2\015\012"); 662 $handle->push_write ("request 2\015\012");
652 663
653 # simply read 64 bytes, always 664 # simply read 64 bytes, always
654 $handle->push_read (chunk => 64, sub { 665 $handle->push_read (chunk => 64, sub {
655 my $response = $_[1]; 666 my $response = $_[1];

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