You don't show the rest of your code (i.e., the 'use' statements and the other necessary modules); I suspect that this is where the failure is coming from. Example of working code: 

#!/usr/bin/perl -w
use strict;
use Fcntl;
use MLDBM qw/DB_File Storable/;

tie my %positions_hash, 'MLDBM', 'positions.db', O_CREAT|O_RDWR, 0640 
+or die "positions.db: $!\n";

%positions_hash = (
    foo     =>  1,
    bar     =>  2,
    qux     =>  3,
);

untie %positions_hash;

[download]

On my system (Ubuntu Linux, AMD64), this creates three files - 'positions.db{,dir,pag}' - exactly as expected.


--
"Language shapes the way we think, and determines what we can think about."
-- B. L. Whorf

In reply to Re: MLDBM tie fails by oko1
in thread MLDBM tie fails by greigite

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