Array and Loop Problem


 
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# 1  
Old 07-29-2010
Array and Loop Problem

I've got this problem, if I modify an array in the loop and print it, everything is fine as long as I stay in the loop. But, when I print it outside the loop, nothing happens... How can I solve this problem?

Here I prepared a sample for you to see my problem;


Code:
zgrw@Rain:~$ cat test
asd
123
13
1234

Code:
zgrw@Rain:~$ cat test.sh
#!/bin/bash

declare -a asd
c=0
cat test | while read line; do
        asd[$c]=$line
        echo ${asd[@]}
        ((c++))
done

echo "I wish you here"
echo ${asd[@]}


Output is;
Code:
zgrw@Rain:~$ ./test.sh 
asd
asd 123
asd 123 13
asd 123 13 1234
I wish you here

zgrw@Rain:~$


Last edited by zgrw; 07-29-2010 at 11:36 AM..
# 2  
Old 07-29-2010
Code:
#!/bin/bash

declare -a asd
c=0
while read line; do
        asd[$c]=$line
        echo ${asd[@]}
        ((c++))
done < test

echo "I wish you here"
echo ${asd[@]}

This User Gave Thanks to vgersh99 For This Post:
# 3  
Old 07-29-2010
wow thanks a lot Smilie

why does it work like this but not with cat?
# 4  
Old 07-29-2010
'cat whatever |' creates a subprocess for the 'while read' - the variables within the subprocess/scope stay local and are not accessible outside the subprocess/scope.
# 5  
Old 07-29-2010
hmm interesting. thank you very much
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