[SOLVED] how to write script to start daemon

BW-userx · 10-12-2016, 09:07 PM

I installed thermald I know I need/should write a script called rc.thermald then add it to rc.local in /etc/rc.d and per-instructions from slackbuilds

Code:

Since this is a daemon, it can be started at boot via /etc/rc.d/rc.local:
  /usr/sbin/thermald

It might be necessary to create /var/run/thermald/ first (depending on your local system setup)

An entry could be added to /etc/rc.d/rc.local_shutdown as well:
  killall thermald

CONFIG_X86_MSR is listed as an (optional) dependency, msr-tools
can be installed from http://01.org/msr-tools via src2pkg (www.src2pkg.net/)
If you installed a previous version of thermald, you may need to uninstall
it and then install this one instead of using upgradepkg.

add a shut down in /etc/rc.d/rc.local_shutdown just adding that line killall thermald???

but I am not even sure what format/syntax to use having cat a few of the rc.xxx files to try and get an idea. it confused me instead. In Void Linux all I got a do is just add a soft link from /etc/sv/daemonName to /var/service and that is it, next reboot it starts, or issue #sv u daemon name and start it right then as well. done deal.

I issued #thermald start to see what I'd see

Code:

bash-4.4# thermald start
Ready to serve requests: Daemonizing.. 1
bash-4.4# ps -aux | grep thermald
root     10382  0.0  0.0 122524  5904 ?        Ssl  20:49   0:00 thermald start
root     10406  0.0  0.0   9644  1852 pts/1    S+   20:49   0:00 grep thermald

but I don't think it actually started

and what is this

Code:

It might be necessary to create /var/run/thermald/ first (depending on your local system setup)

my /var/run states this

Code:

bash-4.4# ls /var/run/thermald
thermald.pid
bash-4.4# cat  /var/run/thermald/thermald.pid
bash-4.4#

it is empty ..

so this being the first time I've actually setup this services in Slackware. well here I am dropping down to newbe status.

Code:

if [ -x /sbin/thermald ] ; then
thermald start
fi

that looks to weak ...

Code:

bash-4.4# ps -aux | grep thermald
root     10382  0.0  0.0 122524  5904 ?        Ssl  20:49   0:00 thermald start
root     11715  0.0  0.0   9644  1816 pts/0    S+   21:17   0:00 grep thermald
bash-4.4# thermald stop
Ready to serve requests: Daemonizing.. 1
bash-4.4# 
bash-4.4# ps -aux | grep thermald
root     10382  0.0  0.0 122524  5904 ?        Ssl  20:49   0:00 thermald start
root     11717  0.3  0.0 122524  5828 ?        Ssl  21:18   0:00 thermald stop
root     11720  0.0  0.0   9644  1820 pts/0    S+   21:18   0:00 grep thermald
bash-4.4# killall thermald
bash-4.4# ps -aux | grep thermald
root     11725  0.0  0.0   9644  1832 pts/0    S+   21:18   0:00 grep thermald

that was just doing to see what I'd see..

Code:

bash-4.4# thermald
Ready to serve requests: Daemonizing.. 1
bash-4.4# 
bash-4.4# ps -aux | grep thermald
root     11859  0.0  0.0 122524  6064 ?        Ssl  21:21   0:00 thermald
root     11886  0.0  0.0   9644  1792 pts/0    S+   21:21   0:00 grep thermald

looks like all I have to do is that bit of code without the start command in it, put it in a rc.thermal script

Code:

if [ -x /sbin/thermald ] ; then
 thermald
fi

then in rc.local

Code:

if [ -x /etc/rc.d/rc.scriptname ]; then
    /etc/rc.d/rc.scriptname start
fi

?????
or just put that if statement in rc.local (which maybe bad pratice)?

a lot of help please.

Richard Cranium · 10-12-2016, 11:09 PM

Well, normally someone would write an /etc/rc.d/rc.thermald script that has "start" and "stop" options. Sometimes there will be "restart" and/or "status" methods.

The "restart" method will normally just call the start and stop functions. Any "status" method will look for a pid file and see if that pid matches a running version of the service.

Here's an example (/etc/rc.d/rc.messagebus)...

Code:

#!/bin/sh
#
# messagebus:   The D-BUS systemwide message bus
#
# description:  This is a daemon which broadcasts notifications of system events \
#               and other messages. See http://www.freedesktop.org/software/dbus/
#
# processname: dbus-daemon

# This is a modified version of the rc.messagebus script distributed with the
# dbus sources.  Thanks to Don Tanner of the GWare <http://gware.org> Project
# for most of the work involved      --Robby Workman <rworkman@slackware.com>


PIDFILE=/var/run/dbus/dbus.pid

start() {
  mkdir -p $(dirname $PIDFILE)
  if ! ps -u messagebus -c | grep -wq dbus-daemon; then
    rm -f $(dirname $PIDFILE)/*
    if [ -x /usr/bin/dbus-uuidgen -a -x /usr/bin/dbus-daemon ] ; then
      echo "Starting system message bus:  /usr/bin/dbus-uuidgen --ensure ; /usr/bin/dbus-daemon --system"
      /usr/bin/dbus-uuidgen --ensure
      /usr/bin/dbus-daemon --system 1> /dev/null
    fi
  fi
}

stop() {
  if [ -e "$PIDFILE" ]; then
    echo "Stopping system message bus..."
    pid=$(cat $PIDFILE)
    kill $pid 1> /dev/null 2> /dev/null
    # Just in case:
    killall dbus-daemon 1> /dev/null 2> /dev/null
    rm -f $PIDFILE
  fi
}

reload() {
  echo "Reloading system message bus configuration..."
  if [ -e "$PIDFILE" ]; then
    pid=$(cat $PIDFILE)
    kill -HUP $pid
  else
    killall -HUP dbus-daemon
  fi
}

status() {
  if ps -u messagebus -c | grep -wq dbus-daemon; then
    echo "System dbus-daemon is running."
  else
    echo "System dbus-daemon is stopped."
  fi
}

# See how we were called.
case "$1" in
  start)
    start
    ;;
  stop)
    stop
    ;;
  restart)
    stop
    start
    echo "You may need to restart your Window Manager to reconnect to the system dbus."
    ;;
  reload)
    reload
    ;;
  status)
    status
    ;;
  *)
    echo $"Usage: $0 {start|stop|restart|reload|status}"
    ;;
esac

Contrak · 10-12-2016, 11:57 PM

I haven't installed thermald before, but I think you should just do what it says.

Quote:

Since this is a daemon, it can be started at boot via /etc/rc.d/rc.local:
/usr/sbin/thermald

Adding /usr/sbin/thermald in rc.local starts the program.
Its like starting a program on the command line.

Quote:

An entry could be added to /etc/rc.d/rc.local_shutdown as well:
killall thermald

Adding killall thermald kills the program at shutdown.
Like on the command line, killall thermald would quit the program.

Overthinking it, maybe?

BW-userx · 10-13-2016, 06:21 AM

Quote:

Originally Posted by Contrak

I haven't installed thermald before, but I think you should just do what it says.

Adding /usr/sbin/thermald in rc.local starts the program.
Its like starting a program on the command line.

Adding killall thermald kills the program at shutdown.
Like on the command line, killall thermald would quit the program.

Overthinking it, maybe?

yeah perhaps I am over thinking it out of not actually knowing the the simplicity of it. looking at all of the other scripts with case statements and if statements and such to check for everything well, conformity is a word that comes to mind. Seeing how thermald is a no hassle daemon. I got it installed on my other OS, Void and when I am pushing my CPU it works rather nicely.

thanks I think I'll try the simplistic approach first and see what happens.

bassmadrigal · 10-13-2016, 06:49 AM

Personally, I would drop the rc.thermald. To me, the rc.program files are beneficial when the startup of the program is a bit more complex, or you might want to turn it on or off. Granted, whether to create an rc.program file or just add a line or few into your rc.local is a personal preference, but based on the simplicity of this program, I'd just add the /usr/sbin/thermald line into your rc.local and be done with it. I don't think you need to worry about checking if it's executable unless you intend to manually change the permissions of the file itself. And unless this program might have issues if shutdown improperly, I don't think you need to worry about an entry in rc.local_shutdown (which doesn't exist until you create it).

KISS approach

BW-userx · 10-13-2016, 07:01 AM

Quote:

Originally Posted by bassmadrigal

Personally, I would drop the rc.thermald. To me, the rc.program files are beneficial when the startup of the program is a bit more complex, or you might want to turn it on or off. Granted, whether to create an rc.program file or just add a line or few into your rc.local is a personal preference, but based on the simplicity of this program, I'd just add the /usr/sbin/thermald line into your rc.local and be done with it. I don't think you need to worry about checking if it's executable unless you intend to manually change the permissions of the file itself. And unless this program might have issues if shutdown improperly, I don't think you need to worry about an entry in rc.local_shutdown (which doesn't exist until you create it).

KISS approach

already done, I deleted my rc.thermald file I created, added to rc.local all except I didn't add the absolute path to thermald and reboot to see if that worked, I just started off the command line in root login. using the word thermald so my brain said brain, just thermald should work it did in the terminal, and i created an rc.local_shutdown and chmod 'ed it. it maybe over kill but that shouldn't hurt anything.

changed to /usr/sbin/termald

thanks...