mysub(\@arrofhash);

sub mysub {
  my @aoh=@{$_[0]};
  $aof[0]->{somekey}++;
  ...
}

##</code><code>##

mysub(@arrofhash);
sub mysub {
  my @aoh=@_;
  $aof[0]->{somekey}++;
  ...
}

##</code><code>##

mysub(%hash);
sub mysub {
  my %args=@_;
  print $args{somekey},"\n";
  ...
}