sub myFunction
{
     my $arg = shift;
     #blah blah blah, do some stuff.....
}
myFunction($myArg);

##</code><code>##

sub myFunction
{
     my $arg = @_;
     #blah blah blah, do some stuff.....
}
myFunction($myArg);

##</code><code>##

sub myFunction
{
     my $arg = $_[0];
     #blah blah blah, do some stuff.....
}
myFunction($myArg);