Can't change permission for bash.bashrc file in Ubuntu

Question

I'm trying to change the permission for my .bashrc file in Ubuntu but don't seem to have permission. I've tried following the example here:

Open up publicity.html for reading and writing by anyone.

Before:  -rw-r--r--  publicity.html
Command: chmod og=rw publicity.html
After:  -rw-rw-rw-  publicity.html

Here's my terminal session:

username@ubuntu:/etc$ -rw-r--r-- bash.bashrc
-rw-r--r--: command not found
username@ubuntu:/etc$ chmod og=rw bash.bashrc
chmod: changing permissions of `bash.bashrc': Operation not permitted
username@ubuntu:/etc$ -rw-rw-rw- bash.bashrc
-rw-rw-rw-: command not found

Any ideas how I can do it?

Answer 1

The file is probably not owned by you. try

sudo chmod og=rw bash.bash.rc

You can see who owns it with

ls -l

and you can change owner with

sudo chown username:username bash.bash.rc

Answer 2

Looks like you entered -rw-r--r-- bash.bashrc as a command.
It's not a command itself but is part the output of the command ls -l bash.bashrc.

Example:

user@host:~$ ls -l /etc/bash.bashrc
-rw-r--r-- 1 root root 1939 2010-04-19 04:15 /etc/bash.bashrc

See Wikipedia for further information on the meaning of -rw-r--r--
http://en.wikipedia.org/wiki/File_system_permissions#Symbolic_notation