Since you get the output you desire when printing to STDOUT, you have a problem with shell redirection, hence yours is not a Perl {question,problem} but a {shell,OS} one.

Or else you may simply have a problem with buffering. Are you trying to read from the file before the writing has terminated? Try adding e.g. $|++ at the top of your script.

Update: OTOH, it doesn't have anything to do with your problem, but generally Perl-style for loops are preferrable over C-style ones. Your script may be rewritten as (untested): 

#!/usr/bin/perl -l

use strict;
use warnings;
use Net::Ping;

my @net=map "192.168.$_",
  qw/97 100 102 104 105 32 33 34/;

my $p=Net::Ping->new or
  die "Can't create ping object: $!\n";

for my $net (@net) {
    for (16..250) {
        my $host="$net.$_";
        warn "$host not responding!\n" and next
          if !$p->ping($host);
        print $host;
    }
}

__END__

[download]
Please note that I also made a few minor, "cosmetic", changes. E.g. I turned a print into a warn. This may not be what you want, but is often appropriate in similar situations.

In reply to Re: Net::Ping and STDOUT by blazar
in thread Net::Ping and STDOUT by yam

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