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Comparing BDB/README (file contents):
Revision 1.5 by root, Wed Dec 12 01:20:54 2007 UTC vs.
Revision 1.7 by root, Sun Mar 30 06:29:07 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 FILENAMES/DATABASE NAMES
93 The BDB expects "binary" filenames (octet strings) for pathnames on
94 POSIX systems, and "unicode" filenames (strings with characters
95 potentially >255) on Win32 (expecting a Unicode win32 build - win32 is a
96 total mess).
97
89 BERKELEYDB FUNCTIONS 98 BERKELEYDB FUNCTIONS
90 All of these are functions. The create functions simply return a new 99 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 100 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 101 callback as last argument. If it is missing, then the function will be
93 executed synchronously. In both cases, $! will reflect the return value 102 executed synchronously. In both cases, $! will reflect the return value
94 of the function. 103 of the function.
95 104
96 BDB functions that cannot block (mostly functions that manipulate 105 BDB functions that cannot block (mostly functions that manipulate
97 settings) are method calls on the relevant objects, so the rule of thumb 106 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 107 is: if it's a method, it's not blocking, if it's a function, it takes a
99 callback as last argument. 108 callback as last argument.
100 109
101 In the following, $int signifies an integer return value, "octetstring" 110 In the following, $int signifies an integer return value, "octetstring"
102 is a "binary string" (i.e. a perl string with no character indices 111 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" 112 >255), "U32" is an unsigned 32 bit integer, "int" is some integer, "NV"
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329 DESTROY (DBC_ornull *dbc) 338 DESTROY (DBC_ornull *dbc)
330 CODE: 339 CODE:
331 if (dbc) 340 if (dbc)
332 dbc->c_close (dbc); 341 dbc->c_close (dbc);
333 342
343 $int = $cursor->set_priority ($priority = PRIORITY_*)
344
334 Example: 345 Example:
335 my $c = $db->cursor; 346 my $c = $db->cursor;
336 347
337 for (;;) { 348 for (;;) {
338 db_c_get $c, my $key, my $data, BDB::NEXT; 349 db_c_get $c, my $key, my $data, BDB::NEXT;
… …
356 flags: SEQ_DEC SEQ_INC SEQ_WRAP 367 flags: SEQ_DEC SEQ_INC SEQ_WRAP
357 $int = $seq->set_range (db_seq_t min, db_seq_t max) 368 $int = $seq->set_range (db_seq_t min, db_seq_t max)
358 369
359 Example: 370 Example:
360 my $seq = $db->sequence; 371 my $seq = $db->sequence;
361 372
362 db_sequence_open $seq, undef, "seq", BDB::CREATE; 373 db_sequence_open $seq, undef, "seq", BDB::CREATE;
363 db_sequence_get $seq, undef, 1, my $value; 374 db_sequence_get $seq, undef, 1, my $value;
364 375
365 SUPPORT FUNCTIONS 376 SUPPORT FUNCTIONS
366 EVENT PROCESSING AND EVENT LOOP INTEGRATION 377 EVENT PROCESSING AND EVENT LOOP INTEGRATION
367 $msg = BDB::strerror [$errno] 378 $msg = BDB::strerror [$errno]
368 Returns the string corresponding to the given errno value. If no 379 Returns the string corresponding to the given errno value. If no
369 argument is given, use $!. 380 argument is given, use $!.
381
382 Note that the BDB module also patches the $! variable directly, so
383 you should be able to get a bdb error string by simply stringifying
384 $!.
370 385
371 $fileno = BDB::poll_fileno 386 $fileno = BDB::poll_fileno
372 Return the *request result pipe file descriptor*. This filehandle 387 Return the *request result pipe file descriptor*. This filehandle
373 must be polled for reading by some mechanism outside this module 388 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 389 (e.g. Event or select, see below or the SYNOPSIS). If the pipe

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