Daemon process delayed ouput

Question

I have an executable file odo.elf that I need to start in a daemon process on a Micozed board (Petalinux distribution). Here is the executable to start|stop|restart the daemon

#!/bin/sh

DAEMON=/mnt/flash/bin/odo.elf
start ()
{
    echo "Starting Odo"
    start-stop-daemon -S -o -x $DAEMON > /var/log/odo.log &             
}
stop ()
{
    echo " Stopping odo"
    start-stop-daemon -K -x $DAEMON
}
restart()
{
    stop
    start
}
[ -e $DAEMON ] || exit 1
    case "$1" in
        start)
            start; ;;
        stop)
            stop; ;;
        restart)
            restart; ;;
        *)
            echo "Usage: $0 {start|stop|restart}"
            exit 1
    esac
exit $?

After starting the process by line command ' odo start' and after opening the log file 'tail -f /var/log/odo.log' I see that the output is displayed with a delay. If I execute odo.elf by command line (with './odo.elf') the stdout is in real time while when I start odo.elf via daemon process the writing on the log file is not in real time.

So far I cannot find any solution Any suggestion, please? Thank you in advance