Thank you for your response Ikegami. I am running Expect in the verbose mode, so I would expect to see any errors spew on the screen. However, I took your advise and added the following two lines after the "kill" command above to see what is being returned:

$exp1->send_slow("$cmd\n");
$exp1->expect($timeout, -re=>'.*');
print "Got return from Expect:\n".$exp1->match()."\n";
[download]

Got command prompt: [root@fc10-test perl]# Sending kill commands to ch
+ild processes:
/bin/kill -INT 4361
Starting EXPECT pattern matching...
 at /home/csit/usr/perl/lib/site_perl/5.10.1/Expect.pm line 561
        Expect::expect('Expect=GLOB(0x93611a0)', 10, '-re', '.*') call
+ed at vpn_client1.pl line 132
        main::sigInt('INT') called at vpn_client1.pl line 100
        eval {...} called at vpn_client1.pl line 100
Got return from Expect:

VPN process 4361 not dead yet
  4361 ?        00:00:00 openvpn

Sending kill -TERM
Sending kill commands to child processes:
/bin/kill -TERM 4361
Starting EXPECT pattern matching...
 at /home/csit/usr/perl/lib/site_perl/5.10.1/Expect.pm line 561
        Expect::expect('Expect=GLOB(0x93611a0)', 10, '-re', '.*') call
+ed at vpn_client1.pl line 132
        main::sigInt('INT') called at vpn_client1.pl line 100
        eval {...} called at vpn_client1.pl line 100
Got return from Expect:

VPN process 4361 not dead yet
  4361 ?        00:00:00 openvpn
[download]

I am running Expect in the verbose mode, so I would expect to see any errors spew on the screen.

Assuming a bourne-ish shell, the error code returned is present in its $? variable. You'll need to output its contents. (To be clear, I don't mean Perl's similar $? variable.)

...Then again, my kill is quite noisy when it fails.

$ kill -INT 21161
bash: kill: (21161) - Operation not permitted

$ echo $?
1
[download]