How to detect if a file is new

I was wondering if anyone knows if there is a way upon commit to detect if the file being committed is a new file.
I wish to implement a process by way of a script run through commitinfo that will block a file from being committed only if it is new, and being added into a certain part of the repository tree.

I can see that once a file has been created, and then cvs add applied, the entry for the new file gets put in the CVS/Entries file as something like this:  /test-file.txt/0/dummy timestamp/-ko/

Locally I can detect it is new by looking for "dummy timestamp"

# CommitFile=test-file.txt
# CommitType=`grep "^/${CommitFile}/" CVS/Entries | cut -d/ -f4`
# echo $CommitType
# dummy timestamp

But when this actually runs on the server something magical must happen as my return is always blank.

Thank you

Norm.