Root emacs weirdness

[notbob]

While learning about linux gutz, I used emacs dired by root to edit
/proc/sys/kernel/dmesg_restrict file from a 1 to a 0.  Opened emacs /
from root, then went to said dir and edited file.  Upon trying to edit
file using e, I get this in the mini-buffer:

Buffer is read-only: #<buffer dmesg_restrict>

.....but, I was then able to edit the file, nonetheless.  ???  File
permissions are 644.  When it came time to save the dmesg_restrict
file using C-x C-s, I get:

Cannot modify backup file  ....something or other.....
IO error writing /proc/sys/kernel/dmesg_restrict: Invalid argument

.....and then do C-x k, I get the std 'still wanna kill buffer'
question (y).  Yet, in the end, the file is modified.  Also, jumping
up to the parent dir (/proc/sys/kernel), I see no back-up file (foo~)
is created.  I tried this 4-5 times, trying to get the first part of
the above error msg and on the 5 try, it DID indicate the file has
been saved (wrote).  !?!?

What the heck is --or is not-- going on??

I'm using emacs 23.3.1 on Slackware 13.37.

nb