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how to delete the lines containing "./."

Hello everyone,

I am new to linux, I know how to delete the one special character in linux, but i don't know how to delete the lines containing character like "./.". hopefully someone could give some instruction.

Thanks a lot

This will preview the changes.

Code:

sed '/\.\/\./d' name_of_your_file

This will create a new file with the changes. Original file will remain as is.

Code:

sed '/\.\/\./d' name_of_your_file > new_file

This will edit the original file

Code:

sed -i '/\.\/\./d' name_of_your_file

Quote:

Originally Posted by kabamaru (Post 4583342)

This will preview the changes.

Code:

sed '/.\/./d' name_of_your_file

This will create a new file with the changes. Original file will remain as is.

Code:

sed '/.\/./d' name_of_your_file > new_file

This will edit the original file

Code:

sed -i '/.\/./d' name_of_your_file

The above code will delete any line containing /
Not only ./.

You'd have to escape . as well:

Code:

sed '/\.\/\./d' file

Thanks a lot, kabamaru, looks like the last one works

Quote:

Originally Posted by linuxon (Post 4583361)

Thanks kabamaru, that deleted everything in the file when I tried it. Is there any other way?

See my code above.

Quote:

Originally Posted by sycamorex (Post 4583360)

The above code will delete any line containing /
Not only ./.

You'd have to escape . as well:

Code:

sed '/\.\/\./d' file

You're right. The funny thing is I wrote it correctly in my terminal, then wrote it 3 times wrong in the post :-/

To get around conflicts with "/" in sed, you can use a different delimiter.

In the substitution command, you can simply use any ascii character (except for newline and null) instead of the slash. I generally like to use "|" myself.

Code:

sed 's|.*\./\..*||' file #for demonstration purposes, it leaves a blank line behind

You can also change the delimiter for the address fields, except that you must precede the first delimiter with a backslash.

Code:

sed '\|\./\.|d' file

Finally, instead of backslash-escaping regex-reserved characters, consider using character class brackets instead. This can often make things more readable, as well as being more proper regex syntax.

Code:

sed '\|[.]/[.]|d' file

Here are a few useful sed references.
http://www.grymoire.com/Unix/Sed.html
http://sed.sourceforge.net/grabbag/
http://sed.sourceforge.net/sedfaq.html
http://sed.sourceforge.net/sed1line.txt

A couple of regular expressions tutorials:
http://mywiki.wooledge.org/RegularExpression
http://www.grymoire.com/Unix/Regular.html