UNIX for Advanced & Expert Users

I'm having problems editing a file...

I've just picked up administration duties of a system and am trying to edit a sourced .cshrc file owned by root. Although I su to root, I can't edit the file (permission denied; not authorized). Permissions are -rwxr-xr-x on the file as well as the directory (also owned by root). I moved up a directory and found that one to be fully open, where I was able to create a file. I checked ownership of that file and found it to belong to nobody.

How is it that I'm the superuser, but act as nobody? Does this sound like an ACL thing? Or some sort of NFS security?

I won't be back on the system until Monday and am trying to gather ideas. Any help would be much appreciated.

Thanks!

It is an NFS security feature. By default, root is denied its usual power. Go to server that owns the filesystem and edit your file there. Or make that server grant your box full root access. The details of how to do this depends on the os involved and you didn't mention yours. So read the docs for the nfs server.