anydbm is a generic interface to variants of the DBM
database -- dbhash(requires
bsddb),
gdbm, or
dbm. If none of these modules is
installed, the slow-but-simple implementation in module
dumbdbmwill be used.
Open the database file filename and return a corresponding object.
If the database file already exists, the whichdb module is
used to determine its type and the appropriate module is used; if it
does not exist, the first module listed above that can be imported is
used.
The optional flag argument can be
'r' to open an existing database for reading only,
'w' to open an existing database for reading and writing,
'c' to create the database if it doesn't exist, or
'n', which will always create a new empty database. If not
specified, the default value is 'r'.
The optional mode argument is the Unix mode of the file, used
only when the database has to be created. It defaults to octal
0666 (and will be modified by the prevailing umask).
A tuple containing the exceptions that can be raised by each of the
supported modules, with a unique exception anydbm.error as
the first item -- the latter is used when anydbm.error is
raised.
The object returned by open() supports most of the same
functionality as dictionaries; keys and their corresponding values can
be stored, retrieved, and deleted, and the has_key() and
keys() methods are available. Keys and values must always be
strings.