You haven't shown the appropriate code to reproduce the issue, and the following works fine for me:

use warnings;
use strict;
use Data::Dumper;
use Net::SFTP::Foreign;
$Data::Dumper::Useqq=1;

die "Usage: $0 SSH_HOST\n" unless @ARGV==1;
my $sftp = Net::SFTP::Foreign->new($ARGV[0]);
$sftp->die_on_error("Unable to establish SFTP connection");

my $fh1 = $sftp->open("/etc/passwd") or die $sftp->error;
while (<$fh1>) {
    print Dumper($_) if /root/ || /wheel/ || /www/; 
}
[download]

To get better help, register an account so that you can edit nodes if necessary (instead of posting several disjoint anonymous nodes) and show a Short, Self-Contained, Correct Example that reproduces the issue - for example you don't show how you create the $sftp object (I have to guess that it's an Net::SFTP::Foreign), and you don't tell us which line is 96. See also How do I post a question effectively?