use strict;
use IPC::Open2;
use IO::Select;

sub sys_read {
   my ($fh) = @_;
   my $blksize = 4096;
   my $len;
   my $data = "";
   my $buff;
 READS:
   while ($len = sysread($fh, $buff, $blksize)) {
      if (!defined $len) {
         next READS if $! =~ /^Interrupted/;
         return undef;
      }
      $data .= $buff;
   }
   return $data;
}

# The tester.pl script calls a web service using lines like this:
#my $ua = LWP::UserAgent->new;
#my $response = $ua->request(POST $uri, [ackhost => $ackhost,
#                                        data => $data,
#                                        pid => $pid]);
my @command = ("/usr/bin/perl", "./tester.pl");

my($wtr, $rdr);  # trying an autovivification this time.
my $pid = open2($rdr, $wtr, @command);
close $wtr;
my @lst;
push @lst, $rdr;
my $timeout = 4.0;

my @ready;
 READLOOP:
while(@ready = IO::Select->new(@lst)->can_read($timeout)) {
    HANDLELOOP:
      foreach my $rh (@ready) {
         # This might block and sysread might be better, but let's see
+..
         my $buff = sys_read($rh);
         print "buff is *$buff*\n";
         close $rh;
         @lst = ();
      }
}

if (scalar(@lst)) {
   print "Timed out with nothing this time\n";
}
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