Get column list from Postgres Query

I want to get the names, the type and the length of all columns in a postgres query using c-api calls.
For example from:
SELECT customers.id, customers.name, transaction.date, transaction.amount FROM customers, transactions

I must get:

customers.id,
customers.name,
transaction.date,
transaction.amount

How can I achieve this??

Thanks in advance

___________________________________
Panos Germanis
Software Engineer
pgermanis@gmail.com
mob: 6944339998

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