topic Re: To read the variable in Operating System - Linux

To read the variable

Piotr Kirklewski — Mon, 26 Mar 2007 06:10:16 GMT

Hi there
I have variable set:

LV=`vgdisplay -v vg00|awk '{if (/LV Name/) {split($3,a,/\//);printf "%s ",a[4]}}
'`

echo $LV

The output looks like that:

lvol1 lvol2 lvol3 lvol4 lvol5 lvol6 lvol7 lvol8

I nead to read the variable contex, character by character so I can eventualy separate all names of lvols and count them.

Perhaps there is a simplier method to count the hov many separate words are there?

Regards

Re: To read the variable

Oviwan — Mon, 26 Mar 2007 06:17:24 GMT

Hey

echo ${LV} | wc -w

for more info check man wc

to read each character do a for loop

for i in ${LV} ; do
echo ${i}
done

Regards

Re: To read the variable

Peter Godron — Mon, 26 Mar 2007 06:17:54 GMT

Hi,
how about :

echo $LV | wc -w

see "man wc"

Re: To read the variable

Senthil Prabu.S_1 — Mon, 26 Mar 2007 06:41:49 GMT

Hi,
you can use wc command to do it with the switch -w.

so in your script, add this line;

echo $LV | wc -m

From wc man;
-m Counts characters

HTH,
Prabu.S

Re: To read the variable

James R. Ferguson — Mon, 26 Mar 2007 07:04:46 GMT

Hi Piotr:

Based upon your questions, and without disrespect, you might find this shell overview helpful:

http://docs.hp.com/en/B2355-90046/B2355-90046.pdf

I would choose the Poxix shell since this is the HP-UX standard. It aligns closely to the Korn shell and Bash (in the Linux world) is another cousin.

A good site for shell scripts and techniques is also:

http://www.shelldorado.com/

Regards!

...JRF...

Re: To read the variable

Ralph Grothe — Mon, 26 Mar 2007 08:23:45 GMT

Though the thread has been closed already,
but because no one mentioned the use of an array in this context.
You could slightly modify your assignment to

e.g.

# set -A LV $(vgdisplay -v vg00|awk '/LV Name/{split($3,a,/\//);print a[4]}')

# echo ${#LV[*]}
10

Re: To read the variable

Piotr Kirklewski — Mon, 26 Mar 2007 08:32:12 GMT

cool :)