awk trouble inside another command

UNIX for Advanced & Expert Users
1

I tried running this.

dsh -w server1 'lsof /audit | awk '{ print $2 }''

It did not like above so I tried to escape the single parenthesis at the end.

dsh -w server1 'lsof /audit | awk '{ print $2 }\''

It then hung so I changed up the parenthesis to this. This worked.

dsh -w server1 "lsof /audit | awk '{ print $2 }'"

I then noticed I needed to add some field separators. This is not working all. I need both colon space, and space all by its self.

dsh -w server1 "lsof /audit | awk 'BEGIN { FS=":" } { print $2 }'"
syntax error The source line is 1.
The error context is
                >>> { <<<
awk: The statement cannot be correctly parsed.

After I get the above to work I like to do this and add the field separator.

dsh -w server1 "kill $(lsof /audit | awk '{print $2}')"
2

I've stayed away because I could not get past the dsh -w
AIX dsh and linux dash (sometimes dsh) do not have a -w option. Per manpages for both. What does that do -- dsh -w ?

So I'm not sure what is going on. Plus the whole code design concept seems to me to be based on 'one-liner' thinking. Which is cool but not always maintainable as you are finding out.
It looks like you are trying to kill processes with files open - somewhere special. What OS and shell are you using?

3

I am using AIX. Normally dsh runs a command against all of your servers in your server list. When you add the -w option to dsh it allows you to select which server you want to run your command on. In my case I want to run my command on server1. I could run my command without the -w option but it would be harder to debug my problem.

I am not very good at using multiple single and double quotes, and escaping. I think that is my issue.

4

Ok, thanks.

Try this to see if it is working the way you want -- before you try killing processes:

dsh -w server1 "lsof /audit | awk '{print $2}' | while read pid; do; echo $pid ; done"

Next try this to see the result. Your process may not have the permissions it needs to kill other processes. I can't know.

dsh -w server1 "lsof /audit | awk '{print $2}' | while read pid; do; kill $pid ; done"

For stuff like this -- In general I usually write a shell script that does what I want. Then I scp a copy to each server; chmod +x the script, then use ssh (similar to dsh) to invoke my script as required on each server. That way I do not get so many single-double quote issues.
on the server.

5

Would

 ... | awk -F\: '{print $2}')"

work? Mayhap with a double \\ .

6

The problem is that the remote code runs within quotes, requiring extra escapes and escape-escapes. Try to run more locally

dsh -w server1 'lsof /audit' | awk '{ print $2 }'

Now the pipe and its right side are outside the quotes and run locally. The drawback is more load on the network.

7

If the only purpose is "kill" then try "fuser -k"

dsh -w server1 "fuser -k /audit"