Coincidentally, I had to use alarm just the other day, and I was also using uptime to test it.

Have you looked at the alarm docs?  It gives a good example where, in conjunction with eval, you can branch on failure or success (ie. alarm did or didn't take place).

Something like this, perhaps (using the code example from alarm with your code):

use strict;
use warnings;

my @MasterMachineIndex = qw(
    # For example ...
    remote_host_1
    remote_host_2
    remote_host_3
);

foreach $Host (@MasterMachineIndex) {
    &ping;  # my subroutine to ping system...works fine

    $Cmd = "rsh $Host uptime";
    my $result = "";
    eval {
        local $SIG{ALRM} = sub { die "alarm\n" }; # NB: \n required
        alarm $timeout;
        $result = `$Cmd`;
        alarm 0;
    };
    if ($@) {
        ($@ eq "alarm\n") or die "Unexpected error\n";
        # Handle timeout here.
    }
    else {
        # Success here.
    }

    # ...
}
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system('ssh', '-o', 'ConnectTimeout 4', '-o', 'SetupTimeout 4', $host,
+ 'cd');
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use Net::Ping;
use POSIX ":sys_wait_h";
my $doping="true";
my pid;

$SIG{ALRM}=\&end_of_time;

foreach $host ( @HOSTS ) {
  # If true ping the host 1st to see if its on the network.
  if ( $doping eq "true" ) {
        $pong = Net::Ping->new( $> ? "tcp" : "icmp", 10);
        (defined $pong )
        or die "Can't create new ping object: $!\n";
        if ( not $pong->ping($host) ) {
                $pong->close;
                print "$host --Dead--\n";
                #go to next host
                next;
                }
  $pong->close;
  }

  ### Set alarm incase processes hang
  alarm $end_of_time;

  ### Do your Checks here
  $pid=....;
    

}

sub end_of_time {
     alarm 0;
     kill => $pid;
     print "----[ EOT Reached Killed shell process [ $shell ] for host
+ [ $host ]----\n";
}
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Thanks for the suggestions. I got it to work. Final solution is below.

Thanks!

-fiddler42

use Mail::Mailer;
use Term::Cap;
use POSIX;

my $TermIOs = new POSIX::Termios; 
$TermIOs->getattr;
my $OSpeed = $TermIOs->getospeed;
my $t = Tgetent Term::Cap { TERM => undef, OSPEED => $OSpeed };
(${norm}, ${bold}, ${under}) = map { $t->Tputs($_,1) } qw/me md us/;

$Timeout = 5;
$Home = "/path/to/my/home";
my @MasterMachineIndex = qw (host1 host host3);

foreach $Host (@MasterMachineIndex) {
    &ping;
    $UptimeCheck = "rsh $Host uptime";
    my $UptimeResult = "";
    eval {
        local $SIG{ALRM} = sub { die "Alarm!\n" };
        alarm $Timeout;
        $UptimeResult = `$UptimeCheck`;
        alarm 0;
    };
    if ($@) {
        ($@ eq "Alarm!\n") or die ("Unexpected error...\n");
        print ("${bold}Problems accessing $Host.${norm}  Skipping...\n
+");
        next;
    } else {
        $CheckHome = ("rsh $Host \"cd $Home\"");
        $HomeStatus = `$CheckHome 2>&1`;    # This captures STDERR and
+ STDOUT outputs that may or may not manifest...
        if ($HomeStatus =~ /No such/) {        # May need to add more 
+keywords here.  Not sure all OSs echo same nomenclature...
            print ("${bold}Home directory not mounted on $Host!${norm}
+  Skipping...\n");
        } else {                                         # e.g. auto-e
+mail admin?
            $CPUScan = "rsh $Host \"~/perl/CPUScan.pl >> ~/cpu.stats\"
+";
            $CHECK = `$CPUScan`;
            print ("$Host:\t$UptimeResult");    
        }
    }
}

sub ping {
    my $os = `uname -a`;
    if ($os =~ /SunOS/) {
        # For the line below, bytes transmitted will be 56+8=64 and 1 
+= # of transactions
        my $p = `ping -s $Host 56 1 | grep 'packet loss'`;
        unless ($p =~ /(\d+)% packet loss/) {
            print ("${bold}Bad Response from $Host.${norm}  Skipping..
+.\n");
            next;
        }
    } elsif ($os =~ /Linux/) {
        my $p = `ping -c 1 -t 1 $Host | grep 'packet loss'`;
        unless ($p =~ /(\d+)% packet loss/) {
            print ("${bold}Bad Response from $Host.${norm}  Skipping..
+.\n");
            next;
        }
    }
    my $loss = $1;
    if ($loss > 50) {
        print ("${bold}High packet loss from $Host.${norm}  Skipping..
+.\n");
        next;
    }
}
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