print man to pdf in booklet layout (printer's pair)

#!/usr/bin/perl
use Getopt::Long;
my $manpage = qq(man);
my $sect=0;
GetOptions("section=i"=>\$sect,
"page=s"=>\$manpage);
system(qq(man -Tps -S $sect $manpage | psbook | psnup -2 | ps2pdf ->
~/Desktop/$manpage.pdf)) if $sect;
system(qq(man -Tps $manpage | psbook | psnup -2 | ps2pdf ->
~/Desktop/$manpage.pdf)) if !$sect;

# -s stands for section number
# -p stands for man page topic