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# 1  
Old 06-07-2012
For loop question
Hi,
I'm trying to put together a small script that will read a txt file that contains a list of two columns. Each column is the name of a folder..
e.g.

AIX Server1
AIX Server2
AIX Server3

Code:
$ for i in `cat /opt/apacheprod/scripts/input/copy_list.txt`
do
PLATFORMVAR=`awk ' { print $1 } ' /opt/apacheprod/scripts/input/copy_list.txt`
SERVERVAR=`awk ' { print $2 } ' /opt/apacheprod/scripts/input/copy_list.txt`
echo $PLATFORMVAR $SERVERVAR
done

The main goal is to use the two variables in the for loop to copy files from one location to another but even if I test with an echo it seems to assign both variables with 3 of each instance like below instead of just 1.. Not sure why that is..

AIX AIX AIX Server1 Server2 Server3
AIX AIX AIX Server1 Server2 Server3
AIX AIX AIX Server1 Server2 Server3
AIX AIX AIX Server1 Server2 Server3
AIX AIX AIX Server1 Server2 Server3


Running this as a ksh on a Solaris machine..
# 2  
Old 06-07-2012
Hi


Code:
$ cat file
AIX Server1
AIX Server2
AIX Server3

Script:
Code:
$ cat test.sh
#!/bin/bash


while read PLATFORMVAR SERVERVAR
do
        echo "PLATFORMVAR: $PLATFORMVAR"
        echo "SERVERVAR: $SERVERVAR"
done < file

Run:
Code:
$ ./test.sh
PLATFORMVAR: AIX
SERVERVAR: Server1
PLATFORMVAR: AIX
SERVERVAR: Server2
PLATFORMVAR: AIX
SERVERVAR: Server3

# 3  
Old 06-07-2012
Hi,
Thanks for the quick reply.. That works perfect for echoing the variables but what I'm really trying to do is the following which is copy a contacts file with in a subfolder and rename it with the prefix of its platform and server name to a new location:

Code:
$ while read PLATFORMVAR SERVERVAR
 do
cp /opt/firewalker/data/$PLATFORMVAR/$SERVERVAR/contacts /opt/apacheprod/scripts/input/$PLATFORMVAR_$SERVERVAR_contacts
done < /opt/apacheprod/scripts/input/copy_list.txt

When I tried the above it only copied the last server in the list and it didn't rename the file..
Last edited by Jazmania; 06-07-2012 at 07:50 AM..
# 4  
Old 06-07-2012
Quote:
Originally Posted by Jazmania
Not sure why that is..

AIX AIX AIX Server1 Server2 Server3
AIX AIX AIX Server1 Server2 Server3
AIX AIX AIX Server1 Server2 Server3
AIX AIX AIX Server1 Server2 Server3
AIX AIX AIX Server1 Server2 Server3


Running this as a ksh on a Solaris machine..
Those are actually three lines and not the three repetition.
awk reads the whole file each time. So you are assigning column 1 of the whole file in PLATFORMVAR and column 2 in SERVERVAR (including new line characters)

If you quote the variables, you will see what goes wrong.
Code:
echo "$PLATFORMVAR" "$SERVERVAR"

for files processing in shell, always prefer the method provided in #2.
# 5  
Old 06-07-2012
Is "contacts" a file or a directory ?
# 6  
Old 06-07-2012
Quote:
Originally Posted by methyl
Is "contacts" a file or a directory ?
Hi,

contacts is actually a file..
# 7  
Old 06-07-2012
The problem is quite simple. An underscore character is a valid character in a variable name. Therefore the variable $PLATFORMVAR_$SERVERVAR_contacts is blank !
We need some curly brackets to delimit the variables. This is good practice in Shell scripting anyway.

Code:
cp /opt/firewalker/data/${PLATFORMVAR}/${SERVERVAR}/contacts /opt/apacheprod/scripts/input/${PLATFORMVAR}_${SERVERVAR}_contacts

This User Gave Thanks to methyl For This Post:
Jazmania
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