Your test will look for a "false" value of either thing. That use of && itself triggers the warning! Say 
if (!defined($username) || !defined($dominio))

[download]
for the effect you want.

Or, I'll just report on how many arguments there are in the first place. 

if (scalar(@ARGV) != 2)

[download]
(more often a range of legal values)

—John

In reply to Re: Validating command-line _parameters_ (not options) by John M. Dlugosz
in thread Validating command-line _parameters_ (not options) by dserodio

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