142

I want to grep smb.conf and see only lines which are not commented.

Improve this question
4

9 Answers 9

Reset to default
232 
grep "^[^#;]" smb.conf

The first ^ refers to the beginning of the line, so lines with comments starting after the first character will not be excluded. [^#;] means any character which is not # or ;.

In other words, it reports lines that start with any character other than # and ;. It's not the same as reporting the lines that don't start with # and ; (for which you'd use grep -v '^[#;]') in that it also excludes empty lines, but that's probably preferable in this case as I doubt you care about empty lines.

If you wanted to ignore leading blank characters, you could change it to:

grep '^[[:blank:]]*[^[:blank:]#;]' smb.conf

or

grep -vxE '[[:blank:]]*([#;].*)?' smb.conf

Or

awk '$1 ~ /^[^;#]/' smb.conf
Improve this answer
13
  • 1
    right answer is: cat /etc/samba/smb.conf | grep ^[^#\;] But anyway Thank you Commented Jan 11, 2013 at 20:09
  • 7
    @denys You're wrong: goldilocks's response in not worst than your. .1 Please avoid using cat ...| syntax!. .2 For whipping empty lines AND lines containing only space, maybe with comments U could use this: grep -v "^ *\(#.*\|\)$" < smb.conf Commented Jan 11, 2013 at 20:14
  • 1
    @F.Hauri: What's wrong with cat ... |? Commented Jan 11, 2013 at 21:51
  • 8
    @EmanuelBerg It's an useless fork. cat file | grep "blah" implie running two binaries through a fifo, while grep "blah" <file do exactly same and bind file naturaly to grep's STDIN . [bash] useless cat is a full featured subject of search through any search engine! -> blog.sanctum.geek.nz/useless-use-of-cat ... for sample Commented Jan 11, 2013 at 22:01
  • 2
    It doesn't do exactly the same. It creates 2 processes and a pipe where 1 process is enough. Read the link given in @F.Hauri's last comment. Commented Jan 11, 2013 at 22:12
5

Vim solution:

:v/^\s*[#\n]/p

I stumbled across this question when trying to find the vim solution myself.

Improve this answer
2
  • 1
    This would also delete lines that starts with blanks. Commented Jun 7, 2019 at 14:57
  • True. I found that useful for config files as lines between comments otherwise fill up the output. If you'd rather keep the blank lines, change the * to + like so: v/^\s+[#\n]/p Commented Jun 8, 2019 at 23:27
5

The pipe to grep in oliver nadj's answer may be eliminated by (assuming GNU grep or compatible):

grep -v "^\s*[#\;]\|^\s*$" <some_conf_file>
Improve this answer
2
  • Second grep i@nadj's looks useless , @goldilocks's answer was more than eough. Commented Oct 13, 2015 at 9:19
  • 1
    I agree that goldilocks's answer was correct. However, I also considered it useful to not show empty lines. Commented Oct 13, 2015 at 17:41
5

These examples might be of use to people. 

[user@host tmp]$ cat whitespacetest
# Line 1 is a comment with hash symbol as first char

# Line 2 is a comment with hash symbol as second char
  # Line 3 is a comment with hash symbol as third char
        # Line 4 is a comment with tab first, then hash
        ; Line 5 is a comment with tab first, then semicolon. Comment char is ;
; Line 6 is a comment with semicolon symbol as first char
[user@host tmp]$

The first grep example excludes lines beginning with any amount of whitespace followed by a hash symbol. 

[user@host tmp]$ grep -v '^[[:space:]]*#' whitespacetest

        ; Line 5 is a comment with tab first, then semicolon. Comment char is ;
; Line 6 is a comment with semicolon symbol as first char
[user@host tmp]$

The second excludes lines beginning with any amount of whitespace followed by a hash symbol or semicolon.

[user@host tmp]$ grep -v '^[[:space:]]*[#;]' whitespacetest

[user@host tmp]$
Improve this answer
3 
grep -v "^\s*[#;]" any.conf | grep -v "^\s*$"

that is what works for me. ignore commented or empty lines, even whitespace before hash mark or semicolon

Improve this answer
0

Here i got better one (assuming GNU grep or compatible):

grep -v '^[#;/%<]\|^\s*$' anyfile.conf

exclude for lines which begins with #;/%< which are in square brackets and the second filter after pipe is \s*$ for blank lines.

Improve this answer
1
  • 2
    In what type of conf files are < or / used for comments? I know a lot of conf file formats where < is everything but a comment. ! is sometimes used like in X resource files. Commented Mar 16, 2017 at 10:42
-1 
grep -v '^$\|^\s*#' temp

This one's a lot better, I got it from https://stackoverflow.com/questions/17392869/how-to-print-a-file-excluding-comments-and-blank-lines-using-grep-sed

It assumes GNU grep or compatible.

Improve this answer
1
  • The question also considers lines starting with ; as a comment that should be removed. Commented Jun 7, 2019 at 14:56
-2 
egrep -v "^#|^$" anyfile.txt

this command is to grep all info in file excluding comments and blank lines.

Improve this answer
1
  • 3
    Notice that smb.conf also comments with ; Commented Jul 11, 2019 at 18:41
-3

This should display you the file without those lines that begin with #: grep -v "^#" filename

Improve this answer
1
  • This does nothing to lines starting with ;. Commented Jun 7, 2019 at 14:56

You must log in to answer this question.

Start asking to get answers

Find the answer to your question by asking.

Ask question

Explore related questions

See similar questions with these tags.