UNIX for Dummies Questions & Answers

Hi,
I have an expression using grep and nawk that captures the ID number of a given Unix process. It gets printed to screen but I don't know how to declare a variable to this returned value!
For example,

ps -ef|grep $project | grep -v grep | nawk '{print $2}'

This returns my number. How do I declare some variable to equal the output from the above? Do I use xargs?

Then, once I've captured this value, can I perform math operations on it? Is it an integer already?

Thanks.

Use :
counter=`ps -ef|grep $project | grep -v grep | nawk '{print $2}'`

It may be difficult to seen, but your pine is inserted in to ` ` - this is not quote; this character is left from "1" on the keyboard.

You can use counter=$( ... your pipe ..)

Syntax is depending on the shell. See "command substitution" section in the man page.

Thanks for your reply. I'm still a little uncertain about performing any kind of operation on this returned value. I actually only want to determine if there is a processID, and if there is, kill it. (That part I have, using a | xargs kill.) If there isn't a process then just carry on doing whatever comes next in the script.

So I'm trying this:

if ( $processID > 0 ) then ...


but I get an error,
16305: not found

(where 16305 is the value of the variable).
What is it that's not being found?

Should I just make it simpler and compare $processID to null or ""?

Thanks.