how to check register path programatically ?

Hello,
I have a paypal email address field on user registration form which has a path(using autoassign role module) as /seller/register.
I also have a registration form for buyers and i do not want to show this paypal email address field in the registration form for this path /buyer/register.
The paypal field is being printed by some other module so i want to add a "if" statement for that paypal field in that particular module's .module file.
For e.g
if( path== /seller/register)
{
//print paypal field
}

P.S: i am a drupal newbie so if there is some other better way to achieve this i would be more than happy.

Thanks in advance !