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Nested Loop becomes slow

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# 1  
Old 05-29-2009
Nested Loop becomes slow
Hello I have some nested loop to display files and form menu item.

The part of the code is below.

I found that after runnining the script for a while the display becomes very slow.

Does ksh shell provided any easy way to release variables, reinit, etc.

while [[ $MENU_OPTION == "N" ]];do

script=0
town[0]="Start"

#Loop to display Menu Item
#
READ_OPTION="N"
while [[ $READ_OPTION == "N" ]];do
i=0
#Menu Item
clear
for file in `ls x*.txt`; do
{
((i=i+1))

town[$i]=$file
menuitem=$(print ${town[$i]} | sed -e "s/\_/ /g")
mitem=$(print $menuitem | sed -e "s/\.txt/ /g")
if (($i<10)) then
print " \c"
fi
echo "$i ":" $mitem "
}
done
...
done
...

...

..
...
# 2  
Old 05-29-2009
sed may get very slow when you use the /g option, try avoiding it as far as possible, if you can't, try using perl
# 3  
Old 05-30-2009
Not shure if you have choose the most efficient logic in your script but you can try this for the loop:

Code:
for file in x*.txt; do {
  i=$(($i + 1))
  if [ "$i" -lt 10 ]  then
    print " \c"
  fi
  mitem=$(print "$file" | sed -e "s/\_/ /g" -e "s/\.txt/ /g")
  echo "$i : $mitem "
}

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