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Comparing BDB/BDB.pm (file contents):
Revision 1.25 by root, Mon Dec 10 21:19:06 2007 UTC vs.
Revision 1.36 by root, Sat May 10 20:23:06 2008 UTC

… …
24 db_put $db, undef, "key", "data", 0, sub { 24 db_put $db, undef, "key", "data", 0, sub {
25 db_del $db, undef, "key"; 25 db_del $db, undef, "key";
26 }; 26 };
27 db_sync $db; 27 db_sync $db;
28 28
29 # automatic result processing with AnyEvent: 29 # when you also use Coro, management is easy:
30 our $FH; open $FH, "<&=" . BDB::poll_fileno; 30 use Coro::BDB;
31 our $WATCHER = AnyEvent->io (fh => $FH, poll => 'r', cb => \&BDB::poll_cb); 31
32 # automatic event loop intergration with AnyEvent:
33 use AnyEvent::BDB;
32 34
33 # automatic result processing with EV: 35 # automatic result processing with EV:
34 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;
35 37
36 # with Glib: 38 # with Glib:
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107use strict 'vars'; 109use strict 'vars';
108 110
109use base 'Exporter'; 111use base 'Exporter';
110 112
111BEGIN { 113BEGIN {
112 our $VERSION = '1.3'; 114 our $VERSION = '1.5';
113 115
114 our @BDB_REQ = qw( 116 our @BDB_REQ = qw(
115 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
116 db_env_memp_sync db_env_memp_trickle 118 db_env_memp_sync db_env_memp_trickle
117 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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131 133
132 require XSLoader; 134 require XSLoader;
133 XSLoader::load ("BDB", $VERSION); 135 XSLoader::load ("BDB", $VERSION);
134} 136}
135 137
138=head2 WIN32 FILENAMES/DATABASE NAME MESS
139
140Perl on Win32 supports only ASCII filenames (the reason is that it abuses
141an internal flag to store wether a filename is Unicode or ANSI, but that
142flag is used for somethign else in the perl core, so there is no way to
143detect wether a filename is ANSI or Unicode-encoded). The BDB module
144tries to work around this issue by assuming that the filename is an ANSI
145filename and BDB was built for unicode support.
146
136=head2 BERKELEYDB FUNCTIONS 147=head2 BERKELEYDB FUNCTIONS
137 148
138All of these are functions. The create functions simply return a new 149All of these are functions. The create functions simply return a new
139object and never block. All the remaining functions all take an optional 150object and never block. All the remaining functions take an optional
140callback as last argument. If it is missing, then the function will be 151callback as last argument. If it is missing, then the function will be
141executed synchronously. In both cases, C<$!> will reflect the return value 152executed synchronously. In both cases, C<$!> will reflect the return value
142of the function. 153of the function.
143 154
144BDB functions that cannot block (mostly functions that manipulate 155BDB functions that cannot block (mostly functions that manipulate
145settings) are method calls on the relevant objects, so the rule of thumb 156settings) are method calls on the relevant objects, so the rule of thumb
146is: if its a method, its not blocking, if its a function, it takes a 157is: if it's a method, it's not blocking, if it's a function, it takes a
147callback as last argument. 158callback as last argument.
148 159
149In the following, C<$int> signifies an integer return value, 160In the following, C<$int> signifies an integer return value,
150C<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
151indices >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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388 DESTROY (DBC_ornull *dbc) 399 DESTROY (DBC_ornull *dbc)
389 CODE: 400 CODE:
390 if (dbc) 401 if (dbc)
391 dbc->c_close (dbc); 402 dbc->c_close (dbc);
392 403
404 $int = $cursor->set_priority ($priority = PRIORITY_*)
405
393=head4 Example: 406=head4 Example:
394 407
395 my $c = $db->cursor; 408 my $c = $db->cursor;
396 409
397 for (;;) { 410 for (;;) {
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434 447
435=item $msg = BDB::strerror [$errno] 448=item $msg = BDB::strerror [$errno]
436 449
437Returns the string corresponding to the given errno value. If no argument 450Returns the string corresponding to the given errno value. If no argument
438is given, use C<$!>. 451is given, use C<$!>.
452
453Note that the BDB module also patches the C<$!> variable directly, so you
454should be able to get a bdb error string by simply stringifying C<$!>.
439 455
440=item $fileno = BDB::poll_fileno 456=item $fileno = BDB::poll_fileno
441 457
442Return the I<request result pipe file descriptor>. This filehandle must be 458Return the I<request result pipe file descriptor>. This filehandle must be
443polled 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
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671 687
672In short: the parent will, after a short pause, continue as if fork had 688In short: the parent will, after a short pause, continue as if fork had
673not been called, while the child will act as if BDB has not been used 689not been called, while the child will act as if BDB has not been used
674yet. 690yet.
675 691
692Win32 note: there is no fork on win32, and perls emulation of it is too
693broken to be supported, so do not use BDB in a windows pseudo-fork, better
694yet, switch to a more capable platform.
695
676=head2 MEMORY USAGE 696=head2 MEMORY USAGE
677 697
678Per-request usage: 698Per-request usage:
679 699
680Each aio request uses - depending on your architecture - around 100-200 700Each aio request uses - depending on your architecture - around 100-200
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701 TXN_DEADLOCK flag will be set on the transaction. See C<db_txn_finish>, 721 TXN_DEADLOCK flag will be set on the transaction. See C<db_txn_finish>,
702 above. 722 above.
703 723
704=head1 SEE ALSO 724=head1 SEE ALSO
705 725
706L<Coro::BDB>, L<IO::AIO>. 726L<AnyEvent::BDB> (event loop integration), L<Coro::BDB> (more natural
727syntax), L<IO::AIO> (nice to have).
707 728
708=head1 AUTHOR 729=head1 AUTHOR
709 730
710 Marc Lehmann <schmorp@schmorp.de> 731 Marc Lehmann <schmorp@schmorp.de>
711 http://home.schmorp.de/ 732 http://home.schmorp.de/

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