If you are trying to run a CGI script but need to know the path of perl or sendmail, we provide that for you here.  Note that this is the current configuration across all of our shared hosting servers, but is subject to change in the future (though highly unlikely).

Sendmail: /usr/sbin/sendmail

Perl: /usr/bin/perl (first line of script should show: #!/usr/bin/perl)

PHP (You probably won't need this): /usr/bin/php