use strict;
use warnings;

if (1) {   
   local *FH;
   my $fh = \*FH;
   open $fh, 'ls /usr |';
}

$_ = <FH>;

warn $_;
__END__
ls: write error
readline() on unopened filehandle FH at - line 10.
Use of uninitialized value $_ in warn at - line 12.
Warning: something's wrong at - line 12.

##</code><code>##

use strict;
use warnings;

{
    open my $fh, 'ls /usr |';
}
warn "End\n";
__END__
ls: write error
End