Other than processing options using Getopt::Long (which I use most frequently) and Getopt::Std, options can be parsed manually. For example, in your case: 
my ($input,$stat,$csv);
while (my $arg = shift @ARGV) {
if ($arg eq "-i") {
 $input = shift @ARGV;
} elsif ($arg eq "-s") {
 $stat = shift @ARGV;
} elsif ($arg eq "-o") {
 $csv = shift @ARGV;
} else {
 die "$arg: invalid argument\n";
}
defined $input && defined $csv && defined $stat || die "You should def
+ine -i, -o and -s!\n";

[download]
You can also use 5.010 and process arguments in "switch-case" style.
Sorry if my advice was wrong.

In reply to Re: Perl Input Parameters for Unix by aitap
in thread Perl Input Parameters for Unix by Anonymous Monk

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