Your problem is that the default is for the tie DB_File call to create a new file. The following excerpt is taken from the DB_File docs:
tie %A, "DB_File", "filename" ;
is equivalent to:
tie %A, "DB_File", "filename", O_CREAT|O_RDWR, 0666, $DB_HASH ;
Try it without the implied O_CREAT argument: 
tie (%HASH, "DB_File", $filename, O_RDWR) or die "Can't open $filename
+: $!\n";

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In reply to RE: GDBM files by lhoward
in thread GDBM files by Ovid

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