Set screensaver using script.

The tilde (~) expansion will apply against the user running the script. When you run your script locally in Terminal its applying against your account, since you're running it. When it runs from Casper. its using the service account or root (typically the latter) As such, since all your paths start with ~/, you're telling your script to apply the settings to "root" and not who is logged in.
You need to get the logged in user account in your script up front, and then use that account as the path to the plist files to affect.

That said, I think you should be able to accomplish what you want with either Configuration Profiles or MCX and not have to use a recurring script at all. That's what they are designed for, so I would look into those first before attempting to script it.

Update:
I simply can't get it to work using Casper. I've been trying to use Managed Preferences as well.
The script below works while running it from the terminal as the current user.

Any input or directions are more than welcome.

#!/bin/sh
# grab current user
curUser=`ls -l /dev/console | cut -d " " -f 4`

# grab the system's uuid
if [[ `ioreg -rd1 -c IOPlatformExpertDevice | grep -i "UUID" | cut -c27-50` != "00000000-0000-1000-8000-" ]]; then
    macUUID=`ioreg -rd1 -c IOPlatformExpertDevice | grep -i "UUID" | cut -c27-62`
fi

#jamf displayMessage -message $curUser

defaults write /Users/$curUser/Library/Preferences/ByHost/com.apple.screensaver.$macUUID.plist CleanExit "YES"
defaults write /Users/$curUser/Library/Preferences/ByHost/com.apple.screensaver.$macUUID.plist PrefsVersion -int 100
defaults write /Users/$curUser/Library/Preferences/ByHost/com.apple.screensaver.$macUUID.plist idleTime -int 600
defaults write /Users/$curUser/Library/Preferences/ByHost/com.apple.screensaver.$macUUID.plist moduleDict -dict moduleName "iLifeSlideshows" path "/System/Library/Frameworks/ScreenSaver.framework/Resources/iLifeSlideshows.saver" type -int 0
defaults write /Users/$curUser/Library/Preferences/ByHost/com.apple.ScreenSaverPhotoChooser.$macUUID.plist identifier "/Library/Screen Savers/CORP"
defaults write /Users/$curUser/Library/Preferences/ByHost/com.apple.ScreenSaverPhotoChooser.$macUUID.plist LastViewedPhotoPath "/Library/Screen Savers/CORP"
defaults write /Users/$curUser/Library/Preferences/ByHost/com.apple.ScreenSaverPhotoChooser.$macUUID.plist SelectedFolderPath "/Library/Screen Savers/CORP"
defaults write /Users/$curUser/Library/Preferences/ByHost/com.apple.ScreenSaverPhotoChooser.$macUUID.plist SelectedSource -int 4
defaults write /Users/$curUser/Library/Preferences/ByHost/com.apple.ScreenSaverPhotoChooser.$macUUID.plist ShufflesPhotos -int 1
defaults write /Users/$curUser/Library/Preferences/ByHost/com.apple.ScreenSaver.iLifeSlideShows.$macUUID styleKey "ShiftingTiles"
defaults write /Users/$curUser/Library/Preferences/ByHost/com.apple.ScreenSaver.iLifeSlideShows styleKey "ShiftingTiles"
#sudo chown -R "$curUser:DOMAINDomain Users" ~/Library/Preferences/ByHost/

@bvandepol, as @mm2270 suggested, since the script is running as 'root' I'm pretty sure your line to grab the current user is returning 'root' instead of the user actually using/logging into the system. I second @mm2270's suggestion of utilizing a configuration profile instead of a script for this.

However, if a script is the best way to go for your environment, I would suggest that you modify your package to deploy a LaunchAgent plist that executes your script instead of trying to do it via Casper Policy. As LaunchAgents are run as the logging-in user, you know it will execute in that context.

Thanks @ahambidge for your response. The funny thing is that ```
jamf displayMessage -message $curUser
``` does actually show the correct username.

I'm pretty new to all of this so forgive my ignorance.

I've been looking at Managed Preferences -> Screen Saver (ByHost/Loginwindow) but I can't get it to work there either.

I'm missing the com.apple.ScreenSaver.iLifeSlideShows and com.apple.ScreenSaverPhotoChooser preferences there which I need for our config. The manual settings that I can add are applied/applicable to com.apple.screensaver.ByHost am I right?

Coming from a position as a Windows Sysadmin i find this very frustrating and complex.

@bvandepol][/url, not a problem. I'm currently the workstation Windows & Mac admin at my workplace, so I somewhat understand your frustration. :)

I wouldn't bother with Managed Preferences. While some may continue to get them to work, Apple keeps threatening that they 'may not work in the next release' and I've seen spotty (at best) execution of them myself. Apple released Configuration Profiles as a replacement for Managed Preferences, so I would focus my efforts on that rather than MCX/Managed Preferences, but I'm sure someone smarter than me will chime in to the contrary shortly. :)

In regards to your script snippet utilizing the jamf displayMessage verb; whom are you running that as? Your account via SUDO, or via a Casper policy and capturing the output? I still think the policy is running as root and that's why it's not working. :)

I've never messed with the screensaver, save for it's timeout feature, and I utilized defaults & the default user template to manage it post-image:

#!/bin/sh 
#Sets Screensaver lock settings
defaults write /System/Library/User Template/English.lproj/Library/Preferences/com.apple.screensaver askForPasswordDelay -string 1800
defaults write /System/Library/User Template/English.lproj/Library/Preferences/com.apple.screensaver askForPassword -int 1
echo "Screensaver Settings complete."

AFAIK, these settings still work. It would be pretty simple for you to modify your current script to and remove the "$currUser" variable & path to hardcode in the default user template.

Here is setting the default picture screen saver in perl. which you should be able to convert to shell if you so choose:

unless(-e $ss) {
    syslog('notice', "Setting default ScreenSaver");
    system("defaults -currentHost write com.apple.screensaver moduleDict -dict moduleName "iLifeSlideshow" path "/System/Library/Frameworks/ScreenSaver.framework/Resources/iLifeSlideshows.saver" type 0");
    system("defaults -currentHost write com.apple.ScreenSaverPhotoChooser LastViewedPhotoPath """);
    system("defaults -currentHost write com.apple.ScreenSaverPhotoChooser SelectedFolderPath "/Library/Screen Savers/Default Collections/GreenSaver"  ");
    system("defaults -currentHost write com.apple.ScreenSaverPhotoChooser SelectedSource -int 3");
    system("defaults -currentHost write com.apple.ScreenSaverPhotoChooser ShufflesPhotos -bool false");
    system("touch "$ss"");
}

That was the magic trick!

sudo killall cfprefsd

Thanks all for thinking with me!

Sorry to reopen an old thread,

but is this still viable for 10.11 10.12 and/or 10.13?

This was working great for me until 10.13.4. As soon as any of our machines get updated to 10.13.4 it starts displaying the "Message" Screensaver only.

Did something change with the

defaults write /Users/$currentUser/Library/Preferences/ByHost/com.apple.ScreenSaver.iLifeSlideShows.$macUUID styleKey "Classic" command in 10.13.4?

#!/bin/bash
defaults write /Users/$currentUser/Library/Preferences/ByHost/com.apple.ScreenSaver.iLifeSlideShows.$macUUID styleKey "Classic"

First of all. Please. Switch away from writing into user preference files. This feels so wrong. And you need to kill cfprefsd. And you need to correct permissions. Use user preference domains instead. Run it with sudo in front of it:

#!/bin/bash
sudo $currentUser defaults -currentHost write com.apple.ScreenSaver.iLifeSlideShows styleKey "Classic"

This should solve the problem:

#!/bin/bash
sudo $currentUser defaults -currentHost write com.apple.ScreenSaver.Basic MESSAGE "Put your message here"