append a line to text file in script
 

Hi I am modifying a script and I need a command to add a line to the end of the /etc/modules file. It currently reads like this

I need to get it to look like this

with a carriage return after ath_pci so it ends on a new line.

can someone help?

First do a backup of the original file somewhere, for example
then simply echo the string and append it to the end of the file:

When I type sudo echo ath_pci >> /etc/modules I keep getting the message bash: /etc/modules: permission denied
I thought if I used sudo it should give me permission to do this

I had thought that sudo was for enabling a user to run certain SW--but not to bypass permissions. (I never use it, so I'm not sure.)

Why not just "su" to get root powers? Especially when developing a script, you want to test things the way the script will run.

Using redirection with sudo should take some care. Your command line executes the echo command with root privileges then tries to store the output in /etc/modules as regular user. From the sudo man page there is an useful example:
So you have to spawn the process in a subshell, using