Gpsd设置固定波特率

修改/etc/init.d/gpsd，支持/etc/init.d/gpsd start/stop/restart

#!/bin/sh
### BEGIN INIT INFO
# Provides:          gpsd
# Required-Start:    $remote_fs $syslog $network
# Should-Start:      bluetooth dbus udev
# Required-Stop:     $remote_fs $syslog $network
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# X-Start-Before:    ntp
# Short-Description: GPS33 (Global Positioning System) daemon 
# Description:       The gpsd service daemon is able to monitor one or
#                    more GPS devices connected to a host computer, making
#                    all data on the location and movements of the sensors
#                    available to be queried on TCP port 2947.
### END INIT INFO

# Author: Bernd Zeimetz <bzed@debian.org>
#
# Please remove the "Author" lines above and replace them
# with your own name if you copy and modify this script.

# Do NOT "set -e"

# PATH should only include /usr/* if it runs after the mountnfs.sh script
RUNDIR=/run/gpsd
PATH=/sbin:/usr/sbin:/bin:/usr/bin
DESC="GPS2 (Global Positioning System) daemon"
NAME=gpsd
DAEMON=/usr/sbin/$NAME
PIDFILE=$RUNDIR/$NAME.pid
SCRIPTNAME=/etc/init.d/$NAME

# Exit if the package is not installed
[ -x "$DAEMON" ] || exit 0

# Read configuration variable file if it is present
[ -r /etc/default/$NAME ] && . /etc/default/$NAME

if [ -z "$GPSD_SOCKET" ] && [ -z "$DEVICES" ]; then
	GPSD_SOCKET=/var/run/gpsd.sock
fi

if [ -n "$GPSD_SOCKET" ]; then
        GPSD_OPTIONS="$GPSD_OPTIONS -F $GPSD_SOCKET"
fi

# Load the VERBOSE setting and other rcS variables
. /lib/init/vars.sh

# Define LSB log_* functions.
# Depend on lsb-base (>= 3.0-6) to ensure that this file is present.
. /lib/lsb/init-functions

#
# Function that starts the daemon/service
#
do_start()
{
	# Return
	#   0 if daemon has been started
	#   1 if daemon was already running
	#   2 if daemon could not be started
	baudrate=115200
        mkdir -p $RUNDIR || return 2

	start-stop-daemon --start --quiet --pidfile $PIDFILE --exec $DAEMON --test > /dev/null \
		|| return 1
	while [ $baudrate -ne 9600 ]
	do
		baudrate=`stty speed 9600 -F $DEVICES`
	done	

	start-stop-daemon --start --quiet --pidfile $PIDFILE --exec $DAEMON -- \
		$GPSD_OPTIONS -P $PIDFILE $DEVICES \
		|| return 2
}

#
# Function that stops the daemon/service
#
do_stop()
{
	# Return
	#   0 if daemon has been stopped
	#   1 if daemon was already stopped
	#   2 if daemon could not be stopped
	#   other if a failure occurred
	start-stop-daemon --stop --quiet --retry=TERM/30/KILL/5 --pidfile $PIDFILE --name $NAME
	RETVAL="$?"
	[ "$RETVAL" = 2 ] && return 2
	# Many daemons don't delete their pidfiles when they exit.
	rm -f $PIDFILE
	return "$RETVAL"
}

#
# Function that sends a SIGHUP to the daemon/service
#
do_reload() {
	#
	# If the daemon can reload its configuration without
	# restarting (for example, when it is sent a SIGHUP),
	# then implement that here.
	#
	start-stop-daemon --stop --signal 1 --quiet --pidfile $PIDFILE --name $NAME
	return 0
}

case "$1" in
  start)
        if [ "$START_DAEMON" = "true" ]; then
		[ "$VERBOSE" != no ] && log_daemon_msg "Starting $DESC" "$NAME"
		do_start
		case "$?" in
			0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
			2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
		esac
	else
		[ "$VERBOSE" != no ] && \
			log_daemon_msg "Not starting $DESC" "$NAME" && \
			log_end_msg 0
	fi
	;;
  stop)
	[ "$VERBOSE" != no ] && log_daemon_msg "Stopping $DESC" "$NAME"
	do_stop
	case "$?" in
		0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
		2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
	esac
	;;
  status)
       status_of_proc "$DAEMON" "$NAME" && exit 0 || exit $?
       ;;
  reload|force-reload)
	log_daemon_msg "Reloading $DESC" "$NAME"
	do_reload
	log_end_msg $?
	;;
  restart)
	#
	# If the "reload" option is implemented then remove the
	# 'force-reload' alias
	#
	log_daemon_msg "Restarting $DESC" "$NAME"
	do_stop
	case "$?" in
	  0|1)
		do_start
		case "$?" in
			0) log_end_msg 0 ;;
			1) log_end_msg 1 ;; # Old process is still running
			*) log_end_msg 1 ;; # Failed to start
		esac
		;;
	  *)
	 	# Failed to stop
		log_end_msg 1
		;;
	esac
	;;
  *)
	echo "Usage: $SCRIPTNAME {start|stop|status|restart|force-reload}" >&2
	exit 3
	;;
esac

:

修改systemd文件 /lib/systemd/system/gpsd.service支持service gpsd start/stop/restart

[Unit]
Description=GPS (Global Positioning System) Daemon
Requires=gpsd.socket
# Needed with chrony SOCK refclock
After=chronyd.service

[Service]
Type=forking
EnvironmentFile=-/etc/default/gpsd
ExecStartPre=/bin/stty speed 115200 -F $DEVICES
ExecStart=/usr/sbin/gpsd $GPSD_OPTIONS $DEVICES

[Install]
Also=gpsd.socket