use warnings;
use strict;
use File::Temp qw/tempfile/;

my $fh = File::Temp->new();

print "$_\n" for 0 .. 4;

$fh->seek( 0, 0 );

print for <$fh>;

close $fh

##</code><code>##

0
1
2
3
4

##</code><code>##

...
use IO::File;

my $fh = IO::File->new_tmpfile or die $!;
...