use strict;
use warnings;
use Net::SNMP qw(:snmp);

my $address                 = $ARGV[0];
my $user                    = $ARGV[1];
my $pass                    = $ARGV[2];
my $protocol                = lc $ARGV[3];
my $snmp_community          = $ARGV[4];
my $snmp_version            = $ARGV[5];
my $snmp_port               = $ARGV[6];
my $snmp_timeout            = $ARGV[7];
my $max_oids                = $ARGV[8];
my $snmp_username           = $ARGV[9];
my $snmp_password           = $ARGV[10];
my $snmp_auth_protocol      = $ARGV[11];
my $snmp_priv_passphrase    = $ARGV[12];
my $snmp_priv_protocol      = $ARGV[13];
my $snmp_context            = $ARGV[14];
my $action                  = lc $ARGV[15];
my $type                    = lc $ARGV[16];

my ( $session, $error ) = Net::SNMP->session(
    hostname      => $address,
    port          => $snmp_port,
    version       => "snmpv" . $snmp_version,
    timeout       => $snmp_timeout,
    debug         => $snmp_debug_mask,
    username      => $snmp_username,
    authpassword  => $snmp_password,
    authprotocol  => $snmp_auth_protocol,
    privpassword  => $snmp_priv_passphrase,
    privprotocol  => $snmp_priv_protocol,
);


##</code><code>##

my ( $session, $error ) = Net::SNMP->session(
    ...
    if ($snmp_priv_passphrase ne "") { privpassword  => $snmp_priv_passphrase, }
    ...
}

##</code><code>##

if ($snmp_priv_passphrase ne "") { $snmp_priv_passphrase = undef; }
my ( $session, $error ) = Net::SNMP->session(
    ...
}