function hello(x){print "hello " x ", how are you"}
{hello($1)}

#!/usr/bin/perl
eval 'exec /usr/bin/perl -S $0 ${1+"$@"}'
    if $running_under_some_shell;
                        # this emulates #! processing on NIH machines.
                        # (remove #! line above if indigestible)

eval '$'.$1.'$2;' while $ARGV[0] =~ /^([A-Za-z_0-9]+=)(.*)/ && shift;
                        # process any FOO=bar switches

$, = ' ';               # set output field separator
$\ = "\n";              # set output record separator

while (<>) {
    ($Fld1) = split(' ', $_, 9999);
    &hello($Fld1);
}

sub hello {
    local($X) = @_;
    print 'hello ' . $X . ', how are you';
}