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.