How to retrieve N lines of a text field.

Hi all;

This is a complex issue, and i am tryign to figure out how to use regular
expressions to resolve this issue.  I need to retrieve the first N lines of
a text field.  N would be assigned using a parameterized query, if possible.

I had thought about using something like:
select substring(test from '#"' || repeat('%\n', $1) || '#"%' for '#') from
multiline_test;
However, this always selects every line but the final one (because %\n seems
to be interpreted to be the largest possible string, while I want it to be
the smallest possible string).

Is there a workaround?  Any other help?  Or do I need to write a UDF?

Best Wishes,
Chris Travers