Shell Programming and Scripting

hi there I have a script which outputs hundreds of lines with a servername in each line

eg

Code:

# cat output.txt
server1,problem
server2,problem
server3,problem
server4,problem
server5,problem
server6,problem
server7,problem
server8,problem
...
...

this gets auto-emailed everyday, but our support guys dont want to recieve a list of all servers that have a problem. Whilst they are aware of the issues with, for example, server1 and server3, they dont want to be mailed every day about it, as such, id like to create a file with a list of servers to exclude from the output. eg

Code:

# cat exclude.txt
server1
server3

before emailing my output, id like to perform a kind of 'grep -v' against this file so that my support guys only get mailed about stuff that there not already aware of, so the output would be

Code:

server2,problem
server4,problem
server5,problem
server6,problem
server7,problem
server8,problem
...
...

Is there an easy way of doing this

try:

Code:

grep -v "`cat exclude.txt`" output.txt

Another solutions:

Code:

grep -v -f exclude.txt output.txt

Code:

awk -F, 'NR==FNR{a[$0];next}!($1 in a)' exclude.txt output.txt

Regards

Code:

$ egrep -v 'server1|server3' output.txt
server2,problem
server4,problem
server5,problem
server6,problem
server7,problem
server8,problem

thanks guys