Binary package “libgdbm-dev” in ubuntu focal
GNU dbm database routines (development files)
GNU dbm ('gdbm') is a library of database functions that use extendible
hashing and works similarly to the standard UNIX 'dbm' functions.
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The basic use of 'gdbm' is to store key/data pairs in a data file, thus
providing a persistent version of the 'dictionary' Abstract Data Type
('hash' to perl programmers).
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Note, that to build old programs, that use legacy 'dbm' interface,
you have to install libgdbm-compat-dev binary package.