topic Re: using for loop in Operating System - HP-UX

using for loop

fahad_8 — Sun, 22 Jan 2006 06:01:27 GMT

how to get the size for more than one disk in one script ..?
what i did is
1- ioscan -funCdisk >>f1
2- cat f1|grep rdsk|awk{'print$2'}>f2
3- for i in 'cat f2'
do
diskinfo $i>>f3
done
4- cat f3|grep size>>f4
5-cat size.out|awk{'print $2'}>f5
6- f5 output , it contains only numbers , i want to use script to calculate the sum of these number ??

waiting for reply
thanx

Re: using for loop

Jakes Louw — Sun, 22 Jan 2006 08:10:20 GMT

Try this :

TOTAL=0
for i in `ioscan -funCdisk | grep rdsk | awk ' { print $2 } '`
do
NUMBER=`diskinfo $i | grep size | awk ' { print $2 } '`
# that gives you the size of one disk, now add it to the running total
eval TOTAL=($TOTAL+$NUMBER)

done

echo $TOTAL

Just check my syntax on the eval statement, I always get that wrong.

Re: using for loop

john korterman — Sun, 22 Jan 2006 10:04:48 GMT

Hi,

to sum up:
# awk '{s += $1}END {print s}' < f5

regards,
John K.

Re: using for loop

James R. Ferguson — Sun, 22 Jan 2006 11:36:30 GMT

Hi:

Beware that a simple summation of the values returned by 'diskinfo' by walking the output of 'ioscan', is going to count alternate links (pvlinks) more than once, inflating the amount of disk you think you have.

Also, if you fail to skip unmounted CD|DVDROM devices, the 'diskinfo' query will hang.

Regards!

...JRF...

Re: using for loop

Jeffrey L. Cooke — Mon, 23 Jan 2006 08:14:30 GMT

Although ioscan has a limited amount of output, in situations where I don't know the quantity of output I use 'while'. First redirect the output into a file (as you did) and then read the input from stream 3 (an unused stream) as in this example (working for the other folks answers):

#!/usr/bin/ksh
TOTAL=0
ioscan -funCdisk 2/dev/null |\
grep rdsk|\
awk '{print $NF}'\
>ioscan.txt
while read -u3 i; do
SIZE=$(diskinfo $i|\
grep size|\
awk '{ print $2}'\
)
(( TOTAL = TOTAL + SIZE ))
done 3print -- "$TOTAL"
rm -f ioscan.txt

Re: using for loop

MarkSyder — Mon, 23 Jan 2006 08:26:20 GMT

for i in `ls /dev/rdsk`
do
diskinfo $i|grep -E "describe|size" >> outputfile
done

will do the first part for you.

Mark Syder (like the drink but spelt different)