[SOLVED] Basis SED script won't run from cli using '\' characters

JockVSJock · 06-13-2016, 06:07 PM

Experimenting with SED and trying to get this rum from the CLI:

Code:

sed -n \
-e '/^root/ p' \ 
-e '/^nobody/ p' \ 
/etc/passwd

Once entering the final line of /etc/passwd and pressing return, nothing is returned to the screen.

I have to press ctrl + c to break out of this.

I realize the \ allows me to start a new line. However I'm not understanding why this isn't working.

thanks

dab1414 · 06-13-2016, 07:09 PM

Quote:

Originally Posted by JockVSJock

Code:

sed -n \
-e '/^root/ p' \ 
-e '/^nobody/ p' \ 
/etc/passwd

did you try as single line?
change to, pretty sure there should be no space after regex

Code:

sed -n \
-e '/^root/p' \ 
-e '/^nobody/p' \ 
/etc/passwd

EDIT: I just tried as you wrote, and it worked perfect, same as my suggestion. I was able to do this with a regular user with no privileges. Are you able to cat /etc/passwd with no problems.

keefaz · 06-13-2016, 07:53 PM

Make sure you don't put a space after the \

JockVSJock · 06-13-2016, 08:34 PM

I got it to work. IMO, the example was a bad.

First, you have to be root to run this, since root has access to /etc/passwd, and not a regular user account.

This is how I wrote it up, and no spaces after '\'

Code:

sed -n \
> -e '/^root/ p' \ 
> -e '/^nobody/ p' \
> /etc/passwd

Notice after the first line the ">" character appears. Something to do with the stdout, correct?

dab1414 · 06-13-2016, 09:27 PM

Quote:

Originally Posted by JockVSJock

I got it to work. IMO, the example was a bad.

First, you have to be root to run this, since root has access to /etc/passwd, and not a regular user account.

You should not have to be root. I created a new user with no privileges, and was able to see ouput of this command. Same concept I can nano /etc/passwd as any user just can't write.

Quote:

Originally Posted by JockVSJock

This is how I wrote it up, and no spaces after '\'

Code:

sed -n \
> -e '/^root/ p' \ 
> -e '/^nobody/ p' \
> /etc/passwd

This happened to me when I first copied your code. Didn't dawn on me to mention that.

Quote:

Originally Posted by JockVSJock

Notice after the first line the ">" character appears. Something to do with the stdout, correct?

Check this out, helped me understand it better. Basically second line is PS2 prompt.
https://linuxconfig.org/bash-prompt-basics