Porting from PL/SQL to PLPGSQL

Hi All,

We are in the process of migrating of our application from Oracle to
PostGreSQL.

we are facing a few problems with PL/SQL Code..

1) In Oracle sqlplus we can run sql script files as @script_name;
How do we do the same in PostGres.
Also is there any replacement for "&&" in PostGres ?

Eg:
CREATE USER CATALOG
IDENTIFIED BY &ORA_PASSWORD
DEFAULT TABLESPACE &DFLT_TABLESPACE
TEMPORARY TABLESPACE &TEMP_TABLESPACE

2) In PostGres a function can not take more 16 arguments.We have some
procedures which are taking more than
16 arguements.So how can we convert them into PostGres.

Can anyone give some valuable suggestions..

Regards

Joe.