I assume the best way to set my SSMS (SQL Server 2005) output file path during runtime of T-SQL, is to use SQLCMD mode.

How do I use environment variables (e.g. %systemroot%) in the code? The following bombs:

<code>
:set mypath %systemroot%
:out $(mypath)"\the_result.txt"
select * from myTab
</code>

In other words, when using SQLCMD not from the command line, but inside my T-SQL code.
I just need to sort out the syntax.

(And also perhaps, though forum protocol is probably to ask it as separate questions: 

1. Is there an environment variable for the folder of this .sql / the working folder?

2. How do I prevent the line counts to go to my output file also?
)

Thanks!