topic Re: scripting question in Operating System - HP-UX

scripting question

Igor Sovin — Tue, 12 Sep 2006 03:34:42 GMT

Hi!

My scrpit is the following:
while read host;
do
ssh -n ${host}
done < hostlist.txt

hostlist.txt contains:

hostname2 12 Sep 12:00
hostname3 12 Sep 13:00

How to make shell get only hostname from string, so would be able to ssh hostname1 then hostname2 etc.?

Re: scripting question

Murat SULUHAN — Tue, 12 Sep 2006 04:03:13 GMT

Hi Igor

for i in `cat hostlist.txt | awk '{print $1}'
do
....
......
...
done

Best Regards

Re: scripting question

Peter Godron — Tue, 12 Sep 2006 04:08:14 GMT

or if you see man read
match the number of parameters to the number of fields

while read host a b c

which means hostname is read into host, the rest into a b and c, whcih can be ignored.

Re: scripting question

Tim D Fulford — Tue, 12 Sep 2006 04:12:24 GMT

cat hostlist.txt | perl -ane '{print "$F[0] "}'

would print the hostname. (you could use awk too if you like)

for host in $(cat hostlist.txt | perl -ane '{print "F[0] "}'
do
ssh -n $host
done

or as you have done it as a read..
while read host;
do
ssh -n ${host}
done < $(cat hostlist.txt | perl -ane '{print "F[0] "}'

Regards

Tim

Re: scripting question

Hemmetter — Tue, 12 Sep 2006 04:18:05 GMT

Hi Igor

try:
while read host restofline;
do
ssh -n ${host}
done < hostlist.txt

This will assign the first "word" to $host and the rest of the line to $restofline.

rgds
HGH

Re: scripting question

Igor Sovin — Tue, 12 Sep 2006 04:56:11 GMT

Thanks a lot guys!
All suggestions are quite good!