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Comparing BDB/BDB.pm (file contents):
Revision 1.30 by root, Tue Dec 25 14:23:21 2007 UTC vs.
Revision 1.37 by root, Mon Jul 7 14:28:53 2008 UTC

… …
27 db_sync $db; 27 db_sync $db;
28 28
29 # when you also use Coro, management is easy: 29 # when you also use Coro, management is easy:
30 use Coro::BDB; 30 use Coro::BDB;
31 31
32 # automatic result processing with AnyEvent: 32 # automatic event loop intergration with AnyEvent:
33 our $FH; open $FH, "<&=" . BDB::poll_fileno; 33 use AnyEvent::BDB;
34 our $WATCHER = AnyEvent->io (fh => $FH, poll => 'r', cb => \&BDB::poll_cb);
35 34
36 # automatic result processing with EV: 35 # automatic result processing with EV:
37 my $WATCHER = EV::io BDB::poll_fileno, EV::READ, \&BDB::poll_cb; 36 my $WATCHER = EV::io BDB::poll_fileno, EV::READ, \&BDB::poll_cb;
38 37
39 # with Glib: 38 # with Glib:
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110use strict 'vars'; 109use strict 'vars';
111 110
112use base 'Exporter'; 111use base 'Exporter';
113 112
114BEGIN { 113BEGIN {
115 our $VERSION = '1.42'; 114 our $VERSION = '1.5';
116 115
117 our @BDB_REQ = qw( 116 our @BDB_REQ = qw(
118 db_env_open db_env_close db_env_txn_checkpoint db_env_lock_detect 117 db_env_open db_env_close db_env_txn_checkpoint db_env_lock_detect
119 db_env_memp_sync db_env_memp_trickle 118 db_env_memp_sync db_env_memp_trickle
120 db_open db_close db_compact db_sync db_upgrade 119 db_open db_close db_compact db_sync db_upgrade
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134 133
135 require XSLoader; 134 require XSLoader;
136 XSLoader::load ("BDB", $VERSION); 135 XSLoader::load ("BDB", $VERSION);
137} 136}
138 137
138=head2 WIN32 FILENAMES/DATABASE NAME MESS
139
140Perl on Win32 supports only ASCII filenames (the reason is that it abuses
141an internal flag to store wether a filename is Unicode or ANSI, but that
142flag is used for somethign else in the perl core, so there is no way to
143detect wether a filename is ANSI or Unicode-encoded). The BDB module
144tries to work around this issue by assuming that the filename is an ANSI
145filename and BDB was built for unicode support.
146
139=head2 BERKELEYDB FUNCTIONS 147=head2 BERKELEYDB FUNCTIONS
140 148
141All of these are functions. The create functions simply return a new 149All of these are functions. The create functions simply return a new
142object and never block. All the remaining functions all take an optional 150object and never block. All the remaining functions take an optional
143callback as last argument. If it is missing, then the function will be 151callback as last argument. If it is missing, then the function will be
144executed synchronously. In both cases, C<$!> will reflect the return value 152executed synchronously. In both cases, C<$!> will reflect the return value
145of the function. 153of the function.
146 154
147BDB functions that cannot block (mostly functions that manipulate 155BDB functions that cannot block (mostly functions that manipulate
148settings) are method calls on the relevant objects, so the rule of thumb 156settings) are method calls on the relevant objects, so the rule of thumb
149is: if its a method, its not blocking, if its a function, it takes a 157is: if it's a method, it's not blocking, if it's a function, it takes a
150callback as last argument. 158callback as last argument.
151 159
152In the following, C<$int> signifies an integer return value, 160In the following, C<$int> signifies an integer return value,
153C<octetstring> is a "binary string" (i.e. a perl string with no character 161C<octetstring> is a "binary string" (i.e. a perl string with no character
154indices >255), C<U32> is an unsigned 32 bit integer, C<int> is some 162indices >255), C<U32> is an unsigned 32 bit integer, C<int> is some
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440=item $msg = BDB::strerror [$errno] 448=item $msg = BDB::strerror [$errno]
441 449
442Returns the string corresponding to the given errno value. If no argument 450Returns the string corresponding to the given errno value. If no argument
443is given, use C<$!>. 451is given, use C<$!>.
444 452
453Note that the BDB module also patches the C<$!> variable directly, so you
454should be able to get a bdb error string by simply stringifying C<$!>.
455
445=item $fileno = BDB::poll_fileno 456=item $fileno = BDB::poll_fileno
446 457
447Return the I<request result pipe file descriptor>. This filehandle must be 458Return the I<request result pipe file descriptor>. This filehandle must be
448polled for reading by some mechanism outside this module (e.g. Event or 459polled for reading by some mechanism outside this module (e.g. Event or
449select, see below or the SYNOPSIS). If the pipe becomes readable you have 460select, see below or the SYNOPSIS). If the pipe becomes readable you have
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600 611
601=item BDB::set_sync_prepare $cb 612=item BDB::set_sync_prepare $cb
602 613
603Sets a callback that is called whenever a request is created without an 614Sets a callback that is called whenever a request is created without an
604explicit callback. It has to return two code references. The first is used 615explicit callback. It has to return two code references. The first is used
605as the request callback, and the second is called to wait until the first 616as the request callback (it should save the return status), and the second
617is called to wait until the first callback has been called (it must set
618C<$!> to the return status).
619
620This mechanism can be used to include BDB into other event mechanisms,
621such as L<AnyEvent::BDB> or L<Coro::BDB>.
622
606callback has been called. The default implementation works like this: 623The default implementation works like this:
607 624
608 sub { 625 sub {
609 my $status; 626 my $status;
610 ( 627 (
611 sub { $status = $! }, 628 sub { $status = $! },
612 sub { BDB::poll while !defined $status; $! = $status }, 629 sub { BDB::poll while !defined $status; $! = $status },
613 ) 630 )
614 } 631 }
632
633It simply blocks the process till the request has finished and then sets
634C<$!> to the return value. This means that if you don't use a callback,
635BDB will simply fall back to synchronous operations.
615 636
616=back 637=back
617 638
618=head3 STATISTICAL INFORMATION 639=head3 STATISTICAL INFORMATION
619 640
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710 TXN_DEADLOCK flag will be set on the transaction. See C<db_txn_finish>, 731 TXN_DEADLOCK flag will be set on the transaction. See C<db_txn_finish>,
711 above. 732 above.
712 733
713=head1 SEE ALSO 734=head1 SEE ALSO
714 735
715L<Coro::BDB>, L<IO::AIO>. 736L<AnyEvent::BDB> (event loop integration), L<Coro::BDB> (more natural
737syntax), L<IO::AIO> (nice to have).
716 738
717=head1 AUTHOR 739=head1 AUTHOR
718 740
719 Marc Lehmann <schmorp@schmorp.de> 741 Marc Lehmann <schmorp@schmorp.de>
720 http://home.schmorp.de/ 742 http://home.schmorp.de/

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