Shell Script - comparing lines of text, deleting matches

Posted by SirRatty on Stack Overflow See other posts from Stack Overflow or by SirRatty
Published on 2010-04-23T03:53:16Z Indexed on 2010/04/23 4:03 UTC
Read the original article Hit count: 279

Filed under:

shell

|

script

|

text

|

compare

|

diff

Hi all, I've done some searching for this but cannot find what I'm after, specifically.

I have two files: "a.txt", "b.txt".

Each contains a list of email addresses, separated by newlines.

For all lines in "a.txt", I need to check for a match anywhere in "b.txt". If so, the email address in "a.txt" needs to be removed.

(Alternatively, a new file "c.txt" could be created with the output if that is easier.)

I'm using Mac OS X, so am looking for a shell script that could help, or pointers to how I'd go about constructing the script. Thanks for any help.

© Stack Overflow or respective owner

Related posts about shell

How to restrict the users' shell allowing to execute shell programs

as seen on Server Fault - Search for 'Server Fault'
Is it possible to prevent any user to not use commands like ls, rm and other system commands which could harm the system. But the users should be able to execute shell programs. >>> More
Shell extension installation not recognized by Windows 7 64-bit shell

as seen on Stack Overflow - Search for 'Stack Overflow'
I have a Copy Hook Handler shell extension that I'm trying to install on Windows 7 64-bit. The shell extension DLL is compiled in two separate versions for 32-bit and 64-bit Windows. The DLL implements DLLRegisterServer which adds the necessary registry entries. After adding the registry entries… >>> More
Running shell commands without a shell window

as seen on Stack Overflow - Search for 'Stack Overflow'
With either subprocess.call or subprocess.Popen, executing a shell command makes a shell window quicky appear and disappear. How can I run the shell command without the shell window? >>> More
Why can't I reinstall MySQL?

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I've been looking all around the Internet for an answer but didn't find anything. I hope you can help me now. I have a server with MySQL. From one day to another, MySQL didn't let me enter with my root password anymore (accsess denied for user 'root'@'localhost' using password: 'YES'). So I tried… >>> More
Bash/shell script - shell output redirection inside a function

as seen on Stack Overflow - Search for 'Stack Overflow'
function grabSourceFile { cd /tmp/lmpsource wget $1 > $LOG baseName=$(basename $1) tar -xvf $baseName > $LOG cd $baseName } When I call this function The captured output is not going to the log file. The output redirection works fine until I call the… >>> More

Related posts about script

Asset Pipeline acting up

as seen on Stack Overflow - Search for 'Stack Overflow'
Ok, so my asset pipeline has suddenly started acting up on my development machine. JS functions that previously worked are now throwing "not a function" errors.. I know I must be doing something wrong. A minute ago the datatables jquery function was working, then it was throwing an error, then it… >>> More
Rendering ASP.NET Script References into the Html Header

as seen on West-Wind - Search for 'West-Wind'
One thing that I’ve come to appreciate in control development in ASP.NET that use JavaScript is the ability to have more control over script and script include placement than ASP.NET provides natively. Specifically in ASP.NET you can use either the ClientScriptManager or ScriptManager to embed scripts… >>> More
How do I configure Tomcat services in Ubuntu?

as seen on Server Fault - Search for 'Server Fault'
I have created a Tomcat script inside the /etc/init.d directory which is #!/bin/bash # description: Tomcat Start Stop Restart # processname: tomcat # chkconfig: 234 20 80 JAVA_HOME=/usr/java/jdk1.6.0_30 export JAVA_HOME PATH=$JAVA_HOME/bin:$PATH export PATH CATALINA_HOME=/usr/tomcat/apache-tomcat-6… >>> More
Avoid richfaces to send back javascript libraries in the ajax responses

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm using JSF 1.2 with Richfaces, and for every ajax request, the server is sending back the response, whichi is good, but it also contains all the links to the javascript files. I want to improve the performance so I just want the <body> to be returned, because all the javascript files are… >>> More
Whats the difference between running a shell script as ./script.sh and sh script.sh

as seen on Stack Overflow - Search for 'Stack Overflow'
I have a script that looks like this #!/bin/bash function something() { echo "hello world!!" } something | tee logfile I have set the execute permission on this file and when I try running the file like this $./script.sh it runs perfectly fine, but when I run it on the command line like… >>> More