Shell Programming and Scripting

#!/bin/sh
# On Linux systems, /bin/sh is often link to dash or bash, on other unix systems it will be posix shell and stuff here might not work.
LOCKFILE=/home/gav/Desktop/wgetTest/lock/wget.lock
LOGFILE=/home/gav/Desktop/wgetTest/log/wget.log
DDIR=/home/gav/Desktop/wgetTest/
JSONDIR=/home/gav/Desktop/wgetTest/text/new.json
IMAGEDIR=/home/gav/Desktop/wgetTest/display/

if [ -f $LOCKFILE ]; then
printf "%s\n" "Lock file exists on date $(date "+%Y%m%d_%H%M")" >> $LOGFILE
exit 1
fi
while true
do
    cd $DDIR || exit 1
    wget -m -c -nH --cut-dirs=2 --output-file=$LOGFILE --timeout=3 --tries=3 --passive-ftp ftp://usr:pwd@mywesite.com/www/test/images/*
    WEXIT1=$? # we shall catch the exit code of wget, 0 is expected (success)
    wget -m -c -nH --cut-dirs=2 --output-file=$LOGFILE --timeout=3 --tries=3 --passive-ftp ftp://usr:pwd@mywesite.com/www/test/display.json
    WEXIT2=$? # we shall catch the exit code of wget, 0 is expected (success)
    ERROR=$(( $WEXIT1 + $WEXIT2 )) # if the sum of both exit codes
    if [ $ERROR -eq 0 ]; then # is 0 (success both, expected), proceed with mv
         mv images/* $IMAGEDIR # we are not checking for mv status, we hope filesystem will work :) (you could do a $? checking here if required)
         mv display.json $JSONDIR  # we are not checking for mv status, we hope filesystem will work :) (you could do a $? checking here if required)
         rm $LOCKFILE # remove the $LOCKFILE for next itteration since everything succeded.
    else
    printf "%s\n" "A wget error has happend, check $LOGFILE, remove $LOCKFILE by hand and rerun"
   exit 1
   fi
sleep 60
done

rm $LOCKFILE