Shell Programming and Scripting

#!/bin/ksh

TOFIND="file4.txt"
CATEGORY=""

function substring
{
    typeset string="$1" out
    typeset -i offset=$2 length=$3

    while (( offset > 0 ))
    do
        string="${string#?}"
        (( offset = offset - 1 ))
    done

    while (( length > 0 ))
    do
        out="$out${string%${string#?}}"
        string="${string#?}"
        (( length = length - 1 ))
    done

    print "$out"
}

while read LINE
do
        [ -z "$LINE" ] && continue

        if [ $(substring "${LINE}" 0 1) == "[" ]
        then
                CATEGORY="$(substring "$LINE" 1 $((${#LINE}-2)))"
                continue
        fi

        if [ "$LINE" == "$TOFIND" ]
        then
            echo "category is $CATEGORY"
            break
        fi
done < conf.file

case $LINE in
  \[*)
      CATEGORY=${LINE#\[Category}
      CATEGORY=${CATEGORY%]} ;;
  $TOFIND)
      echo "category is $CATEGORY"
      break          
esac

TOFIND="file4.txt"
CATEGORY=
FOUND=false
while read line
do
  case $line in
    \[*)
        CATEGORY=${line#\[Category}
        CATEGORY=${CATEGORY%]} ;;
    $TOFIND)
        echo "category is $CATEGORY"
        FOUND=true
        break          
  esac
done < conf.file
if ! $FOUND; then
  echo "not found"
fi