spool file test.txt

I have to extract the data and create a spool file, the data length is not fixed. What is the best approach of using SET commands if the record length is not fixed. Please help.

Set newpage 0
Set pagesize 0
Set feedback off
Set verify off
Set echo off
Set tab off
Set heading off
Set recsep off
set termout on

Thanks

If you are not able to speficy format by set commands for whatever reason, I would use builtin functions and concatenate operator to produce a comma delimited file usable in windows xcel and for sqlldr like this:

spool file.txt
select substr(col1,1,100)||','||rpad(col2,20,' ')||','||ltrim(col3)||','||col4 from table where ...
spool off