Launchctl difference between load and start, unload and stop

launchd

I was reading through the launchctl man page and have a few questions about its functioning:

What is the difference between load and start, unload and stop?
Where do I find the job label for a daemon, is it in the plist file?

Best Answer

TL;DR

You typically want to use launchctl load -w and launchctl unload -w.
start and stop are usually reserved for testing or debugging a job.

Details

launchctl start <label>: Starts the job. This is usually reserved just for testing or debugging a particular job.
launchctl stop <label>: Stops the job. Opposite of start, and it's possible that the job will immediately restart if the job is configured to stay running.

launchctl remove <label>: Removes the job from launchd, but asynchronously. It will not wait for the job to actually stop before returning, so no error handling on this one.

launchctl load <path>: Loads and starts the job as long as the job is not "disabled."
launchctl unload <path>: Stops and unloads the job. The job will still restart on the next login/reboot.

launchctl load -w <path>: Loads and starts the job while also marking the job as "not disabled." The job will restart on the next login/reboot.
launchctl unload -w <path>: Stops and unloads and disables the job. The job will NOT restart on the next login/restart.

Where do I find the job label for a daemon, is it in the plist file?

Yes, it's in the plist file and it typically matches the filename of the plist file.

Related Solutions

Prevent launchctl from starting a anonymous process

That isn't actually launchctl creating a new process; it's most likely dnsmasq itself. If it fork()s into the background, launchd can't tell; then when it talks to launchd, launchd creates an anonymous entry for it. Make sure dnsmasq doesn't background itself.

(The - listed for the regular launchctl list output indicates that the original dnsmasq process exited.)

How to write to Notification Center from a launchd command

You can send to Notification Centre using Applescript (osascript )in you shell script.

There is a very good thread here that explains the various ways of either running only Applescript as a shell script or being able to mix applescript in with bash, for example.

I created a shell script with:

#!/bin/bash
theDate=`date '+DATE: %m/%d/%y TIME:%H:%M:%S'`

osascript -e "display notification \"$theDate\" with title \"test 1\" subtitle \" sub 1\""

I then created a LaunchDaemon in the same way you have and loaded it without sudo.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>Label</key>
    <string>notifTest</string>
    <key>ProgramArguments</key>
    <array>
        <string>/Users/userName/Documents/notify.sh</string>
    </array>
    <key>RunAtLoad</key>
    <true/>
    <key>StartInterval</key>
    <integer>90</integer>
</dict>
</plist>

Every 90 seconds I get a notification:

enter image description here

The notification icon you will notice is the Script Editors one. Which means the Notification is controlled by the Script Editors Notification settings in Notification Centre