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	$self->{stat} = [ @stat ];
	return 1;
}

=item add_line (DATA)

Append data to the temporary file.  This does not affect the original in
any way until C<commit()> is invoked.

=cut

sub add_line($ $)
{
	my ($self, $line) = @_;
	my $f = $self->{f};

	if (!defined $f) {
		$self->err("Cannot add_line() to an unopened tempfile");
		return undef;
	}
	$self->debug("RDBG about to add a line to $f for $self->{fname}\n");
	if (!(print $f $line)) {
		$self->err("Could not add to the tempfile: $!");
		return undef;
	}
	return 1;
}

=item commit ()

Replace the original file with the temporary copy, to which data may have
been added using C<add_line()>.

B<NOTE:> This method uninitializes the C<File::Append::TempFile> object,
that is, removes B<any> association between it and the original file and
even file name!  The next method invoked on this C<File::Append::TempFile>
object should be C<begin_work()>.

=cut

sub commit($)
{
	my ($self) = @_;
	my $f = $self->{f};

	if (!defined $f || !defined $self->{fname}) {
		$self->err("Cannot commit an unopened tempfile");
		return undef;
	}
	$self->debug("RDBG about to commit $f to $self->{fname}\n");

	# Fix stuff up
	if (defined $self->{stat}) {
		# Mode
		if (!chmod $self->{stat}->[2], $f) {
			$self->err("Could not chmod $self->{stat}->[2] ".
			    "$f: $!");
			return undef;
		}
		# Owner & group
		if (!chown $self->{stat}->[4], $self->{stat}->[5], $f) {
			$self->err("Could not chown $self->{stat}->[4], ".
			    "$self->{stat}->[5], $f: $!");
			return undef;
		}
	}
	
	if (!rename $f, $self->{fname}) {
		$self->err("Renaming $f to $self->{fname}: $!");
		return undef;
	}
	$f->unlink_on_destroy(0);
	close $f;
	$self->debug("RDBG successfully committed $f to $self->{fname}\n");
	$self->{fname} = $self->{f} = undef;
	return 1;
}

=item rollback ()

Discard all the changes made to the temporary copy and remove it.  This
does not affect the original file in any way.

B<NOTE:> This method uninitializes the C<File::Append::TempFile> object,
that is, removes B<any> association between it and the original file and
even file name!  The next method invoked on this C<File::Append::TempFile>
object should be C<begin_work()>.

=cut

sub rollback($)
{
	my ($self) = @_;

	$self->debug(ref($self)."->rollback() for $self->{fname}\n");
	if (defined $self->{f}) {
		my $f = $self->{f};
		$self->debug("RDBG closing and removing $f\n");
		$f->unlink_on_destroy(1);
		close $f;
		undef $self->{f};
	}
	undef $self->{fname};
	$self->debug("RDBG rollback seems complete\n");
	return 1;
}

=back

There are also several methods used internally by the
C<File::Append::TempFile> routines:

=over 4

=item debug (MESSAGE)

Display a diagnostic message to the standard error stream if the output
of diagnostic messages has been enabled.

=cut

sub debug($ $)