Thanks. I've taken a closer look at LWP::Parallel now and have some questions about how it should handle many (most?) HTTPS sites. For now, it seems to return HTTP Status "503 Service Unavailable" for ones that exist and are accessible via other agents. Here is one example: 

#!/usr/bin/perl

use LWP::Parallel::UserAgent;
use LWP::Debug qw(+);
use strict;
use warnings;

my $headers = new HTTP::Headers(
    'User-Agent' => "Mozilla/5.0 (X11; Linux i686) AppleWebKit/537.36 
+(KHTML, like Gecko) Chrome/30.0.1599.66 Safari/537.36",
    ); 
my @requests;
foreach my $url ('https://blog.arduino.cc/feed/') {
    push(@requests, HTTP::Request->new('GET', $url, $headers));
}

# new parallel agent
my $pua = LWP::Parallel::UserAgent->new();
$pua->in_order  (0);  
$pua->duplicates(1);
$pua->timeout   (9);
$pua->redirect  (0);
$pua->max_hosts (5);
$pua->nonblock  (0);

foreach my $req (@requests) {
    if ( my $res = $pua->register ($req, \&handle_answer, 8192) ) { 
    print $res->error_as_HTML; 
    } else {
    print qq(ok\n);
    }
}

my $entries = $pua->wait();
foreach my $k (keys %$entries) {
    my $res = $entries->{$k}->response;
    my $url = $res->request->url;

    print $res->code,qq(\t $url\n);
}

exit(0);

sub handle_answer {
    my($content, $response, $protocol, $entry) = @_;
    if (length($content)) {
        $response->add_content($content);
    }
    return(undef);
}

[download]

As one can see with various browsers the feed in question is there but yet it is one of the feeds that LWP::Parallel is choking on.

In reply to Re^2: IPC::Open, Parallel::ForkManager, or Sockets::IO for parallelizing? by mldvx4
in thread IPC::Open, Parallel::ForkManager, or Sockets::IO for parallelizing? by mldvx4

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