Troubleshooting starting synergyc with systemd

console commands and output

$ sudo systemctl daemon-reload
$ sudo systemctl enable synergyc.service
$ sudo systemctl start synergyc.service
$ sudo systemctl status synergyc.service
● synergyc.service - Start the synergyc client
   Loaded: loaded (/etc/systemd/system/synergyc.service; enabled; vendor preset: enabled)
   Active: active (running) since Fri 2020-03-27 21:06:28 CDT; 5s ago
  Process: 3440 ExecStop=/usr/local/bin/synergyc-ctl.sh stop (code=exited, status=0/SUCCESS)
  Process: 3716 ExecStart=/usr/local/bin/synergyc-ctl.sh start (code=exited, status=0/SUCCESS)
 Main PID: 3730 (synergyc)
    Tasks: 3 (limit: 4915)
   CGroup: /system.slice/synergyc.service
           └─3730 /usr/bin/synergyc --no-tray --name client-name --enable-crypto 192.168.1.73:24800

Mar 27 21:06:25 biagidp-MacPro systemd[1]: Starting Start the synergyc client...
Mar 27 21:06:26 biagidp-MacPro synergyc[3730]: Synergy 1.11.0: [2020-03-27T21:06:26] WARNING: secondary screen unavailable: unable to open screen
Mar 27 21:06:28 biagidp-MacPro systemd[1]: Started Start the synergyc client.

synergyc-ctl.sh

#!/bin/sh
OP=${1}

# put the synergy server IP here (at boot time name lookup does not work
# and synergyc will fail and exit, using the IP prevents the problem)
SERVER_IP=192.168.1.73:24800

SYNERGYC=/usr/bin/synergyc
PS=/bin/ps
GREP=/bin/grep
WC=/usr/bin/wc
PIDOF=/bin/pidof
SLEEP=/bin/sleep

# check synergyc is running
sc_check() {
  N=`${PS} -ef | ${GREP} "${SYNERGYC}"  | ${GREP} -v "${GREP}" | ${WC} -l`
  return $N
}

# kill synergyc if running
sc_kill() {
  SIG=""
  while true
  do
    sc_check
    if [ $? -eq 1 ]
    then
      PIDS=`${PIDOF} "${SYNERGYC}"`
      if [ ${PIDS} != "" ]
      then
        kill ${SIG} ${PIDS}
      fi
    else
      break
    fi

    ${SLEEP} 1
    SIG="-9"
  done
}

# start synergyc
sc_start() {
  COMMAND="${SYNERGYC} --no-tray --name client-name --enable-crypto ${SERVER_IP}"
  while true
  do
    $COMMAND
    ${SLEEP} 2

    sc_check
    if [ $? -eq 1 ]
    then
      break
    fi
  done
}

case "${OP}" in
  start)
    sc_kill
    sc_start
  ;;
  stop)
    sc_kill
  ;;
  *)
    echo "usage: synergyc-ctl [start|stop]"
    exit 1
  ;;
esac

exit 0

synergyc.service

[Unit]
Description=Start the synergyc client

[Service]
ExecStart=/usr/local/bin/synergyc-ctl.sh start
ExecStop=/usr/local/bin/synergyc-ctl.sh stop
Type=forking

[Install]
WantedBy=multi-user.target