Don't know if it actually solves your problem (untested!): 
# creating the packet chunks
my $packet_eth = $ethernet->encode();
my $packet_ip  = $ip->encode();
my $packet = $packet_eth 
   . (0 x (60 - length($packet_eth) - length($packet_ip)))
   . $packet_ip;

[download]
The "x" operator does the right thing when (60 - length($packet_eth) - length($packet_ip)) isn't positive, of course.

30-sec-after update: it would probably pad with character '0' instead of nulls as you want; a quick hack could be: 

# creating the packet chunks
my $packet_eth = $ethernet->encode();
my $packet_ip  = $ip->encode();
my $packet = $packet_eth 
   . (pack 'H*', ('00' x (60 - length($packet_eth) - length($packet_ip
+)))) # Note 0 -> 00
   . $packet_ip;

[download]

Flavio (perl -e 'print(scalar(reverse("\nti.xittelop\@oivalf")))')

Don't fool yourself.

In reply to Re: Creating trailer on packets by polettix
in thread Creating trailer on packets by mosh

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