I am a bit confused by "." and ".."

Suppose i do this:

# ls -l
drwxr-xr-x 86 root root 7520 2006-01-01 07:57 ..
drwxrwxr-x 2 root root 336 2005-05-03 10:59 mydir

It shows the access mode / permissions for the directory 'mydir'
so then i go into mydir and look at the permissions:

# cd mydir
# ls -l
drwxrwxr-x 2 root root 336 2005-05-03 10:59 .
drw-r--r-- 4 root root 360 2005-05-03 10:20 ..
-rw-r--r-- 1 root root 936 2005-04-28 13:05 myfile

I would expect permissions of .. to match those of mydir, but they do not.

How would I change .. to match mydir?

In a listing, "." is the current directory, and ".." is one up.

For example, if you are in /home/fred, and you want to be in /home, you type "cd .." To go up 2 levels" "cd ../.." To go across to /home/mary: "cd ../mary"

"cd ." of course does nothing.

Sooo--to change permissions for "." and "..", simply change the actual directories to which they refer.

The only practical use for "." that I have seen is the "execute here" construct "./program", which tells the system to execute "program" in this directory--don't go looking in $PATH.

)))))))))))))

This is very bad. A directory is absolutely useless without execute permission. It is execute permission which allows you to access the contents of the directory.