negative group permissions?

[jb]

Ian Lepore <freebsd <at> damnhippie.dyndns.org> writes:

> ... 
>  It's not a
> directory or executable file in the first place, so making it executable
> for everyone except the owner and group is not some sort of subtle
> security trick, it's just meaningless.
> ...

Is it meaningless ?

Example:
# cat /var/spool/output/lpd/.seq 
#! /usr/local/bin/bash
touch /tmp/jb-test-`echo $$`

# ls -al /var/spool/output/lpd/.seq 
-rw-r----x  1 root  daemon  54 Feb 29 17:05 /var/spool/output/lpd/.seq
# /var/spool/output/lpd/.seq 
# 
# ls /tmp/jb*
/tmp/jb-test-61789

# chmod 0640 /var/spool/output/lpd/.seq 
# ls -al /var/spool/output/lpd/.seq 
-rw-r-----  1 root  daemon  52 Feb 29 17:11 /var/spool/output/lpd/.seq
# /var/spool/output/lpd/.seq 
su: /var/spool/output/lpd/.seq: Permission denied
#

jb