Re: DB_File modes

[chuckbutler]

in reply to DB_File modes

If you are using a current version of Perl, say > 5.5, using tie %hash is the way to go. Be advised, on some versions/ports tie DOES NOT return the reference to the underlying object of the tie on success. If you are planning to use an extended routine via $ref->routine( ), you may get the reference by $ref = tied(%hash) first. Be sure that the $ref is undef/out-of-scope before you untie %hash. Good luck. -c

[Anonymous Monk]

Be advised, on some versions/ports tie DOES NOT return the reference to the underlying object of the tie on success.

Um, tie always returns the reference to the underlying object, always.

[chuckbutler]

...Mostly on non-Unix platforms. You sometimes receive just a 1, true, on success. I have been burned on this a few times, but then again, I work with a lot of non-Unix distributions. Thanks. -c

[Anonymous Monk]

That is not a very convincing argument.

[Anonymous Monk]

Since you arent going to elaborate, I'll just go ahead and refute your claims

DB_File has contained this code longer than perl 5.5 has existed. The situation you describe is nigh impossible (bless would have to fail and return 1, TIEHASH would have to fail and return 1).

15 May 1997 http://search.cpan.org/~chips/perl5.004/

07 May 1997 http://cpansearch.perl.org/src/PMQS/DB_File-1.14/DB_File.pm

sub TIEHASH
{
    my $pkg = shift ;
 
    bless { VALID => { map {$_, 1} 
               qw( bsize ffactor nelem cachesize hash lorder)
             }, 
        GOT   => {}
          }, $pkg ;
}

If you intentionally return 1 , tied would return undef.

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