rewriting without arrays, line oriented

#!/bin/ksh -px
# get a list of files and dates from ftp and remove files older than ndays

ftpsite="ftp.debian.org"
ftpuser="ftp"
ftppass="ftp"
putdir="/debian"

MM=$(TZ=GMT+29 date +%b)
DD=$(TZ=GMT+29 date +%d)

echo "removing files older than $MM $DD"

 # get directory listing from remote source
echo "
user $ftpuser $ftppass
binary
cd $putdir
ls -l *.txt
quit" | ftp -i -n $ftpsite | while read line; do
    # line is *each line*, rather than a list of everything
    # helps if the filenames have spaces. Just chomp into $0..
    set -- $line
    # month (element 5), day (element 6) and filename (element 8)
    if (($# > 9)); then
        echo "Can't deal with '$@'"
        continue
    fi
    # check the date stamp
    if [[ $5 == "$MM" ]];
    then
        if (($6 < $DD ));
        then
            # Remove this file
            filename=$8
            echo "Removing $filename"

            # replace the ftp with cat with ftp $ftpsite
            cat <<EOMYF2
            ftp -n -i $ftpsite
            user $ftpuser $ftppass
            binary
            cd $putdir
            delete $filename
            quit
EOMYF2
        fi
    fi
done