Dear Monks,

The following code is used to check the status of the network. The logic is, I am executing ping command with two different IP address. If first one failure only, it will goto second one.

#!/usr/bin/perl
use strict;
use warnings;

# register signal.
$SIG{'INT'} = 'Handler';

# declaring variable.
my ($ip1, $ip2, $to, $exit_value1, $exit_value2, $flag);

# this flag is used to avoid the repeat
# execution when execute the second ping
# with second IP address.
$flag=0;

# initializing IP address.
$ip1 = "192.168.0.0";   # first IP address
$ip2 = "google.com";    # second IP address.

# execute the ping with first IP address.
do { eval { $exit_value1 = `ping $ip1`; } };
exit;   # if it is working fine, exit the program.

# execute the ping with second IP address.
Exec:
print "$ip2\n";
$flag=1;    # reset the flag to avoid repeat

# execute second ping with different IP address.
do { eval { $exit_value2 = `ping $ip2`; } };

# it is a signal handle for SIGINT signal.
sub Handler {
    # alert message to user.
    print "Caught SIGINT: $?\n";

    # if the first ping command is failure, goto second,
    if (($? != 0) and ($flag == 0)) {
        goto Exec;
    }
    exit(0);
}
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The if condition in handler is true when the first ping failure. But the goto statement inside if condition does not working. Please tell me where I did the mistake?

Note: I used eval instead of setjmp. I don't get any error or warning message for that.