DBM

        dbmopen %hash, $filename, $permissions;

• There are several different libraries than can handle this association

• Which one did dbmopen use?

  • Whichever one was compiled into Perl

  • If you want to copy data from an NDBM file into an ODBM file, too bad

• This was one of the major motivations for the Perl 5 module system

• New syntax:

        tie %hash, 'Package', ARGS...;

• The Package is a module responsible for implementing the association

• dbmopen %hash, $file is now emulated as

        tie %hash, 'AnyDBM_File';

• AnyDBM_File tries several popular modules until it finds one that works

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Copyright © 2003 M. J. Dominus