Write to ".out" file from shell script.

Question: How to write messages to FND OUT file.?
Ans:
Here are the steps, to write something into fnd out file.
In shell script what ever we echo something that will be written in log file. This is expected behaviour.!
To write some content into ".out" file, one need to do it explicitly.
Here are the steps.
1. findout out file name. which is --> o.out
2. findout out directory name. Mostly $APPLCSF/out or something like this.
3. write the intended content/text to ".out" file.
4. if you are able to write text in .out file correctly, then same can be seen from "View Output" button as soon as concurrent program is completed.

Sample code:
# do sed on f2 and add 'o' and '.out' as suffix and prefix.
OUTFILE_NAME=o`echo $1 cut -d" " -f2 sed 's/FCP_REQID=//g' sed 's/"//g' `.outecho $OUTFILE_NAME
# any other code here ..
# finally write text in to outfile. In my case, I am writing contents of temp.txt to out file.
cat temp.txt >> $APPLCSF/out/$OUTFILE_NAME

..