How can I retrieve an info about function arguments ?

Hello All
Consider a function:
create function f(varchar(10), decimal(10,1)) returns integer as 'select 1;'
language sql;
I need to retreive full set of info about argument and return types (for
variable length too).
How I can get it from system catalog ?
For tables columns I can gen an info from pg_attribute table. But in case of
function no entry are present there.
pg_proc has no info about length of variable length types.

__________________________________________________________________ Dmitry
Vitalievitch ICQ#: 11000008 Current ICQ status: + More ways to contact me
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