LinuxQuestions.org - [SOLVED] grep for multiple strings to exclude

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grep for multiple strings to exclude

Hi,

I'm looking to delete files in a folder. because there many different file names, i thought its best to remove files that do not match the grep statement.

folder looks like this:

Code:



2.txt



dump.2.new.1.txt

dump.2.new.3.txt

dump.2.new.4.txt



dump.2.old.1.txt

dump.2.old.3.txt

dump.2.old.4.txt

i tried the following which worked:

Code:

rm -rf $(ls * | grep -v ^dump.2.new.*)

but ofcourse it delete 2.txt as well.

i've tried the following:

Code:

ls * | grep -v  "^dump.2.new.* | ^2.txt$"

ls * | grep -v  '^dump.2.new.* | ^2.txt$'

which doesn't work (it displays all the files) :(

Can somebody please tell me why this fails?

You have to escape the '|' in your expression for grep to interpret it as a logical OR rather than a literal '|'

Try:

Code:

ls * | grep -v '^dump.2.new.*\|^2.txt'

Also, be careful about your spaces. You might be adding them to make the expression more readable to you, but you may be inadvertently telling grep to match an unintended space.

EDIT:
You can also rewrite the command to separate your matches. For instance, the following command gave me identical results:

Code:

ls * | grep -v -e '^dump.2.new.*' -e '^2.txt'

Quote:

Originally Posted by Dark_Helmet (Post 4542134)

You have to escape the '|' in your expression for grep to interpret it as a logical OR rather than a literal '|'

Try:

Code:

ls * | grep -v '^dump.2.new.*\|^2.txt'

Code:

ls * | grep -v -e '^dump.2.new.*' -e '^2.txt'

Hi, Thanks for your reply.

I tried your suggestion and it doesn't seem to quite work for me.

everytime i run it i get:

Code:

2.txt

dump.2.new.1.txt

dump.2.new.3.txt

dump.2.new.4.txt

dump.2.old.1.txt

dump.2.old.3.txt

dump.2.old.4.txt

my desired output is:

Code:

dump.2.old.1.txt

dump.2.old.3.txt

dump.2.old.4.txt

i tried it both ways but i can't seem to get it to work :confused:

Here is a copy of my terminal run:

Code:

testuser@localhost ~$ ls -l

total 0

-rw-r--r-- 1 testuser testuser 0 Dec  4 21:10 2.txt

-rw-r--r-- 1 testuser testuser 0 Dec  4 21:10 dump.2.new.1.txt

-rw-r--r-- 1 testuser testuser 0 Dec  4 21:10 dump.2.new.3.txt

-rw-r--r-- 1 testuser testuser 0 Dec  4 21:11 dump.2.new.4.txt

-rw-r--r-- 1 testuser testuser 0 Dec  4 21:11 dump.2.old.1.txt

-rw-r--r-- 1 testuser testuser 0 Dec  4 21:11 dump.2.old.3.txt

-rw-r--r-- 1 testuser testuser 0 Dec  4 21:11 dump.2.old.4.txt

testuser@localhost ~$ ls * | grep -v  '^dump.2.new.*\|^2.txt'

dump.2.old.1.txt

dump.2.old.3.txt

dump.2.old.4.txt

testuser@localhost ~$ ls * | grep -v  -e '^dump.2.new.*' -e '^2.txt'

dump.2.old.1.txt

dump.2.old.3.txt

dump.2.old.4.txt

testuser@localhost ~$ grep --version

GNU grep 2.6.3



Copyright (C) 2009 Free Software Foundation, Inc.

License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>

This is free software: you are free to change and redistribute it.

There is NO WARRANTY, to the extent permitted by law.

So, two things:

1. Are you copying the commands exactly as-is AND running them from a terminal exactly as-is?
2. If so, compare your grep version to mine. If yours is different, then that might explain the problem.

EDIT:
Your OS icon next to your posts shows you are running Windows. If you are using Cygwin, I don't know if it includes a port of grep that supports all the features found in a native linux install. I ran the above commands on a Debian system. I have no experience using Cygwin and do not know what limitations it has (if any).

I tried this command and it worked for me

Code:

rm -rf $(ls -l | grep -v 'dump.2.new.*.txt')

Considering that file name has "dump.2.new." and "txt" will be constant and remaining will be variable.

Quote:

Originally Posted by Dark_Helmet (Post 4542156)

Here is a copy of my terminal run:

Code:

testuser@localhost ~$ ls -l

total 0

-rw-r--r-- 1 testuser testuser 0 Dec  4 21:10 2.txt

-rw-r--r-- 1 testuser testuser 0 Dec  4 21:10 dump.2.new.1.txt

-rw-r--r-- 1 testuser testuser 0 Dec  4 21:10 dump.2.new.3.txt

-rw-r--r-- 1 testuser testuser 0 Dec  4 21:11 dump.2.new.4.txt

-rw-r--r-- 1 testuser testuser 0 Dec  4 21:11 dump.2.old.1.txt

-rw-r--r-- 1 testuser testuser 0 Dec  4 21:11 dump.2.old.3.txt

-rw-r--r-- 1 testuser testuser 0 Dec  4 21:11 dump.2.old.4.txt

testuser@localhost ~$ ls * | grep -v  '^dump.2.new.*\|^2.txt'

dump.2.old.1.txt

dump.2.old.3.txt

dump.2.old.4.txt

testuser@localhost ~$ ls * | grep -v  -e '^dump.2.new.*' -e '^2.txt'

dump.2.old.1.txt

dump.2.old.3.txt

dump.2.old.4.txt

testuser@localhost ~$ grep --version

GNU grep 2.6.3



Copyright (C) 2009 Free Software Foundation, Inc.

License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>

This is free software: you are free to change and redistribute it.

There is NO WARRANTY, to the extent permitted by law.

Does this folder(where ever you have tried above command) contains any sub folders ?

Quote:

Originally Posted by Dark_Helmet (Post 4542156)

Here is a copy of my terminal run:

Code:

testuser@localhost ~$ ls -l

total 0

-rw-r--r-- 1 testuser testuser 0 Dec  4 21:10 2.txt

-rw-r--r-- 1 testuser testuser 0 Dec  4 21:10 dump.2.new.1.txt

-rw-r--r-- 1 testuser testuser 0 Dec  4 21:10 dump.2.new.3.txt

-rw-r--r-- 1 testuser testuser 0 Dec  4 21:11 dump.2.new.4.txt

-rw-r--r-- 1 testuser testuser 0 Dec  4 21:11 dump.2.old.1.txt

-rw-r--r-- 1 testuser testuser 0 Dec  4 21:11 dump.2.old.3.txt

-rw-r--r-- 1 testuser testuser 0 Dec  4 21:11 dump.2.old.4.txt

testuser@localhost ~$ ls * | grep -v  '^dump.2.new.*\|^2.txt'

dump.2.old.1.txt

dump.2.old.3.txt

dump.2.old.4.txt

testuser@localhost ~$ ls * | grep -v  -e '^dump.2.new.*' -e '^2.txt'

dump.2.old.1.txt

dump.2.old.3.txt

dump.2.old.4.txt

testuser@localhost ~$ grep --version

GNU grep 2.6.3



Copyright (C) 2009 Free Software Foundation, Inc.

License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>

This is free software: you are free to change and redistribute it.

There is NO WARRANTY, to the extent permitted by law.

Thanks DH.

I think its the version of grep @ work thats incompatible.

I tried it at home and it works like a charm!

Glad it works... at least half the time.

At an old job of mine, we VNC'd into a Linux environment to do work. That environment didn't have all the tools and/or versions I was used to working with. The admins did give us a decent quota and gave us access to gcc. So, if the same is true for your setup, you might do the same thing I did: download the source for the tool(s), compile, and install them locally to your home directory.

You can work your way to an appropriate tarball from here: GNU Grep Page