8.6 Built-in Module dbm

   

The dbm module provides an interface to the Unix (n)dbm library. Dbm objects behave like mappings (dictionaries), except that keys and values are always strings. Printing a dbm object doesn't print the keys and values, and the items() and values() methods are not supported.

See also the gdbm module, which provides a similar interface using the GNU GDBM library.  

The module defines the following constant and functions:

error

Raised on dbm-specific errors, such as I/O errors. KeyError is raised for general mapping errors like specifying an incorrect key.

open (filename, [flag, [mode]])

Open a dbm database and return a dbm object. The filename argument is the name of the database file (without the `.dir' or `.pag' extensions).

The optional flag argument can be 'r' (to open an existing database for reading only -- default), 'w' (to open an existing database for reading and writing), 'c' (which creates the database if it doesn't exist), or 'n' (which always creates a new empty database).

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.