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Comparing BDB/README (file contents):
Revision 1.5 by root, Wed Dec 12 01:20:54 2007 UTC vs.
Revision 1.8 by root, Sun Mar 30 08:01:59 2008 UTC

… …
22 db_put $db, undef, "key", "data", 0, sub { 22 db_put $db, undef, "key", "data", 0, sub {
23 db_del $db, undef, "key"; 23 db_del $db, undef, "key";
24 }; 24 };
25 db_sync $db; 25 db_sync $db;
26 26
27 # when you also use Coro, management is easy:
28 use Coro::BDB;
29
27 # automatic result processing with AnyEvent: 30 # automatic result processing with AnyEvent:
28 our $FH; open $FH, "<&=" . BDB::poll_fileno; 31 our $FH; open $FH, "<&=" . BDB::poll_fileno;
29 our $WATCHER = AnyEvent->io (fh => $FH, poll => 'r', cb => \&BDB::poll_cb); 32 our $WATCHER = AnyEvent->io (fh => $FH, poll => 'r', cb => \&BDB::poll_cb);
30 33
31 # automatic result processing with EV: 34 # automatic result processing with EV:
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84 Request has reached the end of its lifetime and holds no resources 87 Request has reached the end of its lifetime and holds no resources
85 anymore (except possibly for the Perl object, but its connection to 88 anymore (except possibly for the Perl object, but its connection to
86 the actual aio request is severed and calling its methods will 89 the actual aio request is severed and calling its methods will
87 either do nothing or result in a runtime error). 90 either do nothing or result in a runtime error).
88 91
92 WIN32 FILENAMES/DATABASE NAME MESS
93 Perl on Win32 supports only ASCII filenames (the reason is that it
94 abuses an internal flag to store wether a filename is Unicode or ANSI,
95 but that flag is used for somethign else in the perl core, so there is
96 no way to detect wether a filename is ANSI or Unicode-encoded). The BDB
97 module tries to work around this issue by assuming that the filename is
98 an ANSI filename and BDB was built for unicode support.
99
89 BERKELEYDB FUNCTIONS 100 BERKELEYDB FUNCTIONS
90 All of these are functions. The create functions simply return a new 101 All of these are functions. The create functions simply return a new
91 object and never block. All the remaining functions all take an optional 102 object and never block. All the remaining functions take an optional
92 callback as last argument. If it is missing, then the function will be 103 callback as last argument. If it is missing, then the function will be
93 executed synchronously. In both cases, $! will reflect the return value 104 executed synchronously. In both cases, $! will reflect the return value
94 of the function. 105 of the function.
95 106
96 BDB functions that cannot block (mostly functions that manipulate 107 BDB functions that cannot block (mostly functions that manipulate
97 settings) are method calls on the relevant objects, so the rule of thumb 108 settings) are method calls on the relevant objects, so the rule of thumb
98 is: if its a method, its not blocking, if its a function, it takes a 109 is: if it's a method, it's not blocking, if it's a function, it takes a
99 callback as last argument. 110 callback as last argument.
100 111
101 In the following, $int signifies an integer return value, "octetstring" 112 In the following, $int signifies an integer return value, "octetstring"
102 is a "binary string" (i.e. a perl string with no character indices 113 is a "binary string" (i.e. a perl string with no character indices
103 >255), "U32" is an unsigned 32 bit integer, "int" is some integer, "NV" 114 >255), "U32" is an unsigned 32 bit integer, "int" is some integer, "NV"
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329 DESTROY (DBC_ornull *dbc) 340 DESTROY (DBC_ornull *dbc)
330 CODE: 341 CODE:
331 if (dbc) 342 if (dbc)
332 dbc->c_close (dbc); 343 dbc->c_close (dbc);
333 344
345 $int = $cursor->set_priority ($priority = PRIORITY_*)
346
334 Example: 347 Example:
335 my $c = $db->cursor; 348 my $c = $db->cursor;
336 349
337 for (;;) { 350 for (;;) {
338 db_c_get $c, my $key, my $data, BDB::NEXT; 351 db_c_get $c, my $key, my $data, BDB::NEXT;
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356 flags: SEQ_DEC SEQ_INC SEQ_WRAP 369 flags: SEQ_DEC SEQ_INC SEQ_WRAP
357 $int = $seq->set_range (db_seq_t min, db_seq_t max) 370 $int = $seq->set_range (db_seq_t min, db_seq_t max)
358 371
359 Example: 372 Example:
360 my $seq = $db->sequence; 373 my $seq = $db->sequence;
361 374
362 db_sequence_open $seq, undef, "seq", BDB::CREATE; 375 db_sequence_open $seq, undef, "seq", BDB::CREATE;
363 db_sequence_get $seq, undef, 1, my $value; 376 db_sequence_get $seq, undef, 1, my $value;
364 377
365 SUPPORT FUNCTIONS 378 SUPPORT FUNCTIONS
366 EVENT PROCESSING AND EVENT LOOP INTEGRATION 379 EVENT PROCESSING AND EVENT LOOP INTEGRATION
367 $msg = BDB::strerror [$errno] 380 $msg = BDB::strerror [$errno]
368 Returns the string corresponding to the given errno value. If no 381 Returns the string corresponding to the given errno value. If no
369 argument is given, use $!. 382 argument is given, use $!.
383
384 Note that the BDB module also patches the $! variable directly, so
385 you should be able to get a bdb error string by simply stringifying
386 $!.
370 387
371 $fileno = BDB::poll_fileno 388 $fileno = BDB::poll_fileno
372 Return the *request result pipe file descriptor*. This filehandle 389 Return the *request result pipe file descriptor*. This filehandle
373 must be polled for reading by some mechanism outside this module 390 must be polled for reading by some mechanism outside this module
374 (e.g. Event or select, see below or the SYNOPSIS). If the pipe 391 (e.g. Event or select, see below or the SYNOPSIS). If the pipe

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