Notice the scalar reference when using this technique.

#!/usr/bin/perl
#Do you want to use a perl variable as if it were a file?  
#Previous versions of perl had IO::Stringy and IO::Scalar for that.  
#Perl 5.8 with PerlIO has it natively. Just use a reference to  
#the scalar in the filename slot of open. 

my $foo = '';
open FILEHANDLE, '+>', \$foo or die $!;

my $count = 0;
    for(1..100){
    print FILEHANDLE $count;
#    print "$foo\n"; 
#    select(undef,undef,undef,.1); 
     $count++;
}

close FILEHANDLE or die $!;

print "###########################\n";
print "$foo\n";
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