Case statements and vars for bash script

geech · 01-09-2009, 02:46 PM

Can someone please tell me why when this runs that ZIP and FILE are echo'd as nulls at the end? The file test.txt has tons of stuff in it.

FILENAME=test.txt
count=0
cat $FILENAME | while read LINE
do
count=`expr "$count" + 1`
case $count in
"1") ZIP=$LINE;;
"2") FILE=$LINE;;
*)
esac
done
echo $ZIP
echo $FILE

antegallya · 01-09-2009, 04:49 PM

Hello,
it is because when you use a pipe bash start a subshell to execute the while read ...
and so you are not under the scope of your ZIP and FILE variables when you try to echo them and then you get null.
To avoid this you can use a 'for' instead :

Code:

FILENAME=test.txt
count=0
for LINE in "$(cat $FILENAME)"
 do
   count=`expr "$count" + 1`
   case $count in
    "1") ZIP=$LINE;;
    "2") FILE=$LINE;;
    *)
   esac
 done
echo $ZIP
echo $FILE