PostgreSQL Backup Script

Dear all,

I am stuck with database backup.
While using pg_dump the utility asks for password but since I require
this process to be automated the password prompt is giving me
headaches
is their any way by which can pass the password automatically.
Like setting up a variable in php  which passes the password to the
pg_dump utility on prompt this way the whole process of pg_dump would
get automated.
One obvious solution was to use .pgpass but it does not appeal me
because it is again a security threat.
any pointers or help may lead to unlocked secret.

--
With Best Regards,
Vishal Kashyap.
Lead Software Developer,
http://saihertz.com,
http://vishalkashyap.tk