TIEHANDLE and deep recursion

Hi,

I was wondering of some kind soul could tell me what I am doing wrong in the
code below (one module, one test file, minimum case)

I can see why calling print $fh in "sub PRINT" is recursing - but I cannot
find out how to stop it!! Even copying the filehandle (a suggestion via
Google) seems to not work. I've played with "tied" and do not seem to be
able to find the magic to obtain the underlying filehandle so that calling
print() does not immediately redirect to sub PRINT() and thus recurse.



#### SafeFile.pm #####
package SafeFile;
use warnings;

sub TIEHANDLE
{
my ($self, $fh, @options) = @_;
my $data = {
fh => $fh,
@options,
};
return bless $data, $self;
}

sub FETCH {
my ($self) = @_;
return $self->{fh};
}


sub PRINT {
my $self = shift;
my $fh = *{$self->{fh}};
print $fh @_;
}

sub CLOSE
{
my ($self) = @_;
close $self->{fh};
}

sub safewrite {
my $path = shift;
open my $fh, '>', ;
tie *$fh, __PACKAGE__, *$fh,
(
path => $path,
);
return $fh;
}

1;
#### END SafeFile.pm #####

#### test #####
#!/usr/bin/perl
use warnings;

use SafeFile;

my $fh = SafeFile->safewrite('/tmp/wibble');
print $fh "Hello\n";
print $fh "World\n";
close $fh;
#### END test #####


% perl test
#### Result #####
Deep recursion on subroutine "SafeFile::PRINT" at SafeFile.pm line 23.
/bin/bash: line 1: 21037 Segmentation fault perl test

shell returned 139

Press ENTER or type command to continue

#### END Result #####


The purpose of this is to redirect a request to open ...., ">somefile"; to
open ..., ">somefile.tmp";

The filehandle $fh should be usuable normally with print etc.

On close($fh), somefile.tmp is closed, and rename()'d (an atomic operation
on Linux) to "somefile" - thus the target file is never in a half written
state at any point.

Any thoughts would be most welcome :)

Cheers,

Tim



--
Tim Watts
.

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