If you've come to Mac OS X from another Unix, you may expect that you can add users and groups to the /etc/passwd and /etc/group files. By default, Mac OS X only uses these file in single-user mode. If you want to add a user or group, it will need to go into the NetInfo database, a repository of local directory information.
You'll always get Permission Denied when trying to read files which you do not have read-rights for. Error messages like that can easily be avoided though. Just redirect all error mess to /dev/null by adding 2>/dev/null to the end of your command line (2 being the error output stream, 1 being standard out and 0 standard in). i.e
# grep -l whatever /etc/* 2>/dev/null
Operation not permitted is a similar error and is avoided in the same manner
take care/jensa
