LinuxQuestions.org - How to show only uncomment line in the file.

- Linux - Newbie (https://www.linuxquestions.org/questions/linux-newbie-8/)

- - How to show only uncomment line in the file. (https://www.linuxquestions.org/questions/linux-newbie-8/how-to-show-only-uncomment-line-in-the-file-642543/)

How to show only uncomment line in the file.

Can anyone tell my, How to list file content and that line not contain # begin, thank.

$ cat <file> | grep -v "^ *#"
or
$ grep -v "^ *#" <file>

this should do the trick, or sed ...

$ sed '/^ *#/d' <file>

This also ignores leading spaces, removes a line that starts with *any* number of spaces than a comment. If you don't want that you can remove the star from all those line.

The "^" means a start of line, the star means zero or more characters, so " *#" means a start of line with zero or more spaces followed by "#". The "-v" in grep tells grep to remove those lines, and the d in sed tells sed to delete those lines. So if you only like to see those line you could leave out the "-v" in grep.

Hope that helps.

Maybe something like grep may help e.g.

Code:

$grep -i ^[A-Z] somefile

Thank, but not useful in this case.

My file test.txt

Code:

post-proxy {

        #  If you want to have a log of replies from a home server,

        #  un-comment the following line, and the 'detail post_proxy_log'

        #  section, above.

#      post_proxy_log

#      attr_rewrite

        #  Uncomment the following line if you want to filter replies from

        #  remote proxies based on the rules defined in the 'attrs' file.

#      attr_filter

        #

        #  If you are proxying LEAP, you MUST configure the EAP

        #  module, and you MUST list it here, in the post-proxy

        #  stage.

        #

        #  You MUST also use the 'nostrip' option in the 'realm'

        #  configuration.  Otherwise, the User-Name attribute

        #  in the proxied request will not match the user name

        #  hidden inside of the EAP packet, and the end server will

        #  reject the EAP request.

        #

        eap

}

I like to see something like this.

Code:

post-proxy {

        eap

}

@helgiks

Code:

[root@hotspot ~]# cat test.txt | grep -v "^ *#"

post-proxy {

        #  If you want to have a log of replies from a home server,

        #  un-comment the following line, and the 'detail post_proxy_log'

        #  section, above.

        #  Uncomment the following line if you want to filter replies from

        #  remote proxies based on the rules defined in the 'attrs' file.

        #

        #  If you are proxying LEAP, you MUST configure the EAP

        #  module, and you MUST list it here, in the post-proxy

        #  stage.

        #

        #  You MUST also use the 'nostrip' option in the 'realm'

        #  configuration.  Otherwise, the User-Name attribute

        #  in the proxied request will not match the user name

        #  hidden inside of the EAP packet, and the end server will

        #  reject the EAP request.

        #

        eap

}



[root@hotspot ~]#

Code:

[root@hotspot ~]# grep -v "^ *#" test.txt 

post-proxy {

        #  If you want to have a log of replies from a home server,

        #  un-comment the following line, and the 'detail post_proxy_log'

        #  section, above.

        #  Uncomment the following line if you want to filter replies from

        #  remote proxies based on the rules defined in the 'attrs' file.

        #

        #  If you are proxying LEAP, you MUST configure the EAP

        #  module, and you MUST list it here, in the post-proxy

        #  stage.

        #

        #  You MUST also use the 'nostrip' option in the 'realm'

        #  configuration.  Otherwise, the User-Name attribute

        #  in the proxied request will not match the user name

        #  hidden inside of the EAP packet, and the end server will

        #  reject the EAP request.

        #

        eap

}



[root@hotspot ~]#

Code:

[root@hotspot ~]# sed '/^ *#/d' test.txt 

post-proxy {

        #  If you want to have a log of replies from a home server,

        #  un-comment the following line, and the 'detail post_proxy_log'

        #  section, above.

        #  Uncomment the following line if you want to filter replies from

        #  remote proxies based on the rules defined in the 'attrs' file.

        #

        #  If you are proxying LEAP, you MUST configure the EAP

        #  module, and you MUST list it here, in the post-proxy

        #  stage.

        #

        #  You MUST also use the 'nostrip' option in the 'realm'

        #  configuration.  Otherwise, the User-Name attribute

        #  in the proxied request will not match the user name

        #  hidden inside of the EAP packet, and the end server will

        #  reject the EAP request.

        #

        eap

}



[root@hotspot ~]#

@reddazz

Code:

[root@hotspot ~]# grep -i ^[A-Z] test.txt 

post-proxy {

[root@hotspot ~]#

grep -v "#" test.txt works..

Hmm, can't see why those commands I posted are not working for you.

Code:

helgi@desktop:~$> cat > somefile << "EOF"

> post-proxy {

>        #  If you want to have a log of replies from a home server,

>        #  un-comment the following line, and the 'detail post_proxy_log'

>        #  section, above.

> #      post_proxy_log

> #      attr_rewrite

>        #  Uncomment the following line if you want to filter replies from

>        #  remote proxies based on the rules defined in the 'attrs' file.

> #      attr_filter

>        #

>        #  If you are proxying LEAP, you MUST configure the EAP

>        #  module, and you MUST list it here, in the post-proxy

>        #  stage.

>        #

>        #  You MUST also use the 'nostrip' option in the 'realm'

>        #  configuration.  Otherwise, the User-Name attribute

>        #  in the proxied request will not match the user name

>        #  hidden inside of the EAP packet, and the end server will

>        #  reject the EAP request.

>        #

>        eap

> }

> EOF

helgi@desktop:~$> grep -v "^ *#" somefile 

post-proxy {

        eap

}

helgi@desktop:~$>

Works like this on both my Slackware and my Ubuntu :P

EDIT: Is it possible that those comments are just some long lines that don't start with a newline?

Try $ sed 's/^/_/g' <somefile> - and you should see a "_" in the beginning of every line, I think this is your problem, this command should verify that :)

@helgiks, what's this

Code:

[root@hotspot ~]# cp test.txt test2.txt

[root@hotspot ~]# sed 's/^/_/g' test2.txt 

_post-proxy {

_      #  If you want to have a log of replies from a home server,

_      #  un-comment the following line, and the 'detail post_proxy_log'

_      #  section, above.

_#      post_proxy_log

_#      attr_rewrite

_      #  Uncomment the following line if you want to filter replies from

_      #  remote proxies based on the rules defined in the 'attrs' file.

_#      attr_filter

_      #

_      #  If you are proxying LEAP, you MUST configure the EAP

_      #  module, and you MUST list it here, in the post-proxy

_      #  stage.

_      #

_      #  You MUST also use the 'nostrip' option in the 'realm'

_      #  configuration.  Otherwise, the User-Name attribute

_      #  in the proxied request will not match the user name

_      #  hidden inside of the EAP packet, and the end server will

_      #  reject the EAP request.

_      #

_      eap

_}

[root@hotspot ~]#

Maybe there are tabs at the beginning of comment lines. You can try this

Code:

sed '/^[\t ]*#/d' test.txt

It's work, thank you very much.

Code:

[root@hotspot ~]# sed '/^[\t ]*#/d' test.txt

post-proxy {

        eap

}

[root@hotspot ~]#

Ah, there it is...

Than this should do it for you

Code:

$ grep -v "^[[:space:]]*#" <file>

Didn't think about the "other" kind of "space", this will include every kind of space, tab...