Examples 52-53
#Learning Perl Appendix A, Exercise 14.1
#Learning Perl Appendix A, Exercise 14.2
($user,$gcos) = (split /:/)[0,4];
($real) = split(/,/, $gcos);
open(WHO,"who|") || die "cannot open who pipe";
($login, $rest) = /^(\S+)\s+(.*)/;
$login = $real{$login} if $real{$login};
printf "%-30s %s\n",$login,$rest;