IOError - cannot create file (linux daemon-invoked script)

[cassiope]

On Jan 3, 3:00 pm, Cameron Simpson <c... at zip.com.au> wrote:
> On 03Jan2010 14:20, cassiope <f... at u.washington.edu> wrote:
> | On Jan 2, 8:02 pm, Cameron Simpson <c... at zip.com.au> wrote:
> | > Can you show us:
> | >   - the directory user and group ownership and permissions
> | >   - the daemon's user and group values?
> |
> | Directory permissions: 774
>
> That's unusual - why the "4"? Directories with read but no search (1)
> are of limited use. (Not none - it's only unusual, not insane).
>
> | Directory ownership: "lesser user", "special group" where /etc/group
> | has "special group" members including the "lesser user", as well as
> | those who are expected to use the daemon, but not root.
> | Script ownership: "lesser user"; permissions 755
> | Daemon ownership: root; permissions: 755 (always started by root).
>
> And the script/daemon _runs_ as the "lesser user"?
>
> If so, superficially the permissions look like they should work.
> --
> Cameron Simpson <c... at zip.com.au> DoD#743http://www.cskk.ezoshosting.com/cs/
>
> I couldn't think of anything else to do with it, so I put it on the web.

Strace confirms the uid and gid == "lesser user".  Changing the
directory
permissions to 775 changes nothing.  Clearly get EACCES error on the
attempted
file creation.

The only other thing is that as part of the python interpreter call, I
provide
a "reduced environment", just UID,GID,TMP,PWD,USER, and HOME.  Is
anything
else needed?

Thanks again, Cameron!