systemctl stop syslog-ng
/usr/sbin/syslog-ng --syntax-only --cfgfile /etc/syslog-ng/syslog-ng.conf
/usr/sbin/syslog-ng --no-caps --process-mode=background --cfgfile /etc/syslog-ng/syslog-ng.conf --persist-file=/tmp/persist_file --pidfile=/tmp/syslog-ng.pid --control=/tmp/syslog-ng.control >/tmp/syslog_output 2>&1

sleep 2

PID=$(cat /tmp/syslog-ng.pid)

echo "Syslog-ng pid is $PID"

if [ ! -L /proc/$PID/exe ]
then
  echo "syslog-ng could not start"
  exit 1
fi

if [ -s /tmp/syslog_output ]
then
  echo "syslog-ng generated warnings about the config file\n"
  echo "The content of the warnings:"
  cat /tmp/syslog_output
  echo
  exit 1
fi

echo "Syslog-ng was able to start without warnings"

kill $PID
