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Array reference problem

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# 8  
Old 07-19-2010
niteesh that just means your MYHOST variable contains only 1 value namely "tragedy".

so your loop will only take 1 value as it contains only 1 value. if your variable has more than 1 value then your for loop will do more iterations.

Code:
for d in $temp #this temp has only 1value , the loop will run only one time
do 
your code
done

# 9  
Old 07-19-2010
@dazdseg

actually see the situation is this....i agree that myhost has only one value but see the value of temp is

A_<the value in the myhost>
ie A_tragedy
A_tragedy is a predefined array now i need to access members of it
# 10  
Old 07-19-2010
i am not sure, that i am actually getting what you are saying. you mean to say A_tragedy is a pre defined array.
can you show me the input of what exactly your array A_tragedy contains??
As in what are the input members and what is the exact thing you are looking for as an output.
# 11  
Old 07-19-2010
export A_tragedy="1 2 3"
$MYHOST has tragedy
temp has value A_tragedy

now i want to access the members of array A_tragedy using the variable temp and print the array.


thanks in advance
# 12  
Old 07-19-2010
Code:
echo $MYHOST >> TEMP
for word in ${TEMP}
do 
##your code 
done

try this and see if its working because as you are saying it should work
# 13  
Old 07-19-2010
temp is a variable...i append content of $MYHOST to "A_" to get the name of the array,which i store in temp
so,

temp has A_tragedy....ie temp ="A_" appending to $MYHOST
$MYHOST=tragedy
# 14  
Old 07-19-2010
You will have to use "eval", because variable expansion is done in one step in the shell and you need a two-time expansion: you need to expand "A_$MYHOST" to "A_HOSTNAME" and then "$A_HOSTNAME[<nr>]" to the value. See this post for a detailed explanation.

The following example code should tell you what you need:

Code:
typeset hostname="myserver"
typeset -i a_myserver[1]=1
typeset -i a_myserver[2]=2
typeset -i a_myserver[3]=3
typeset -i a_myserver[4]=4
typeset -i a_myserver[5]=5

# Display one value, showing the difference between "\\" and "\":
eval echo \\$a_\$hostname[1] is \${a_$hostname[1]}

# Cycle through all elements of the array: and store to a different array NewArr[]:

typeset iCnt=1
while [ $iCnt -le $(eval echo \${#$hostname[*]}) ] ; do
    typeset NewArr[$iCnt]=$(eval echo \${$hostname[$iCnt]})
    (( iCnt += 1 ))
done

I hope this helps.

bakunin
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