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for loop - reverse reading

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# 1  
Old 02-09-2012
for loop - reverse reading
All,

Here is my for loop
Code:
export CFGLIST="LIST1 LIST2 LIST3"
 
for i in $CFGLIST
do
  echo print $i
done

The output will be
Code:
LIST1
LIST2
LIST3

But i want it display
Code:
LIST3
LIST2
LIST1

Can you please help me how to read in reverse order?

Thanks
Bala
Last edited by Franklin52; 02-09-2012 at 05:33 AM.. Reason: Please use code tags for code and data samples, thank you
# 2  
Old 02-09-2012
Code:
 
a="LIST1 LIST2 LIST3"
$ echo $a | nawk '{for(i=NF;i>=1;i--){print $i}}'
LIST3
LIST2
LIST1

# 3  
Old 02-09-2012
Code:
#!/bin/bash

CFGLIST=(LIST1 LIST2 LIST3)
i=${#CFGLIST[*]}
((i-=1))
while [ $i -ge 0 ]
do
  echo ${CFGLIST[$i]}
  ((i-=1))
done

--ahamed
# 4  
Old 02-09-2012
kamaraj, i'm finding difficulty without nawk - Thanks


Ahamed - if i have as below

CFGLIST=("LIST1 LIST2 LIST3") - It returns same value


Can you please help?

Thanks
Bala
Last edited by baluchen; 02-09-2012 at 08:06 AM..
# 5  
Old 02-09-2012
use awk instead of nawk

---------- Post updated at 05:54 PM ---------- Previous update was at 05:49 PM ----------

Code:
 
$ echo $CFGLIST | perl -lane 'print join(" ",reverse @F)' 
LIST3 LIST2 LIST1

# 6  
Old 02-09-2012
A simple Shell method:

Code:
export CFGLIST="LIST1 LIST2 LIST3"
set ${CFGLIST}
echo "$3"
echo "$2"
echo "$1"

./scriptname
LIST3
LIST2
LIST1

# 7  
Old 02-09-2012
Code:
export CFGLIST="LIST1 LIST2 LIST3"

revlist=
for i in $CFGLIST
do
  revlist="$i $revlist"
done

for i in $revlist
do
  echo "print $i"
done
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