This module is quite similar to the dbm module, but uses gdbm instead to provide some additional functionality. Please note that the file formats created by gdbm and dbm are incompatible.
The gdbm module provides an interface to the GNU DBM library. gdbm objects behave like mappings (dictionaries), except that keys and values are always strings. Printing a gdbm object doesn't print the keys and values, and the items() and values() methods are not supported.
The module defines the following constant and functions:
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).
Appending f to the flag opens the database in fast mode; altered data will not automatically be written to the disk after every change. This results in faster writes to the database, but may result in an inconsistent database if the program crashes while the database is still open. Use the sync() method to force any unwritten data to be written to the disk.
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.
In addition to the dictionary-like methods, gdbm objects have the following methods:
k=db.firstkey() while k!=None: print k k=db.nextkey(k)