I'm a noob to objective c and I have a daemon code that runs as root (system-wide application) and communicates with a server. Every once in a while, the server will command that root app to fire up an additional application that runs within the logged on user context (without interrupting the user - silently).
I have the user context application written as well. What I'm lacking is the understanding on how my root daemon can launch the user context application.
- How can my daemon fire it up on demand?
- Should I use an agent?
- Does it mean the agent will be run at startup?
I've read https://developer.apple.com/library/mac/#technotes/tn2005/tn2083.html as well as http://developer.apple.com/library/mac/#documentation/MacOSX/Conceptual/BPSystemStartup/Chapters/CreatingLaunchdJobs.html but feel I am missing something out.
BTW - the solution should work on 10.6, 10.7, 10.8 ...
Thank you all in advance :o)
This will work if you know current logged in user.
sudo chown -R current_loggedin_user myApp
sudo chmod u+s /Contents/MacOS/myApp
system([@"open myApp" UTF8String]); //inside root process
If the s group of permissions has the user bit set (corresponding to u+s), then whenever anyone executes that program, the process takes on the privileges of whoever owns it. So current_loggedin_user is owner of myApp, open will run myApp in current_loggedin_user mode.
s The set-user-ID-on-execution and set-group-ID-on-execution bits.
u The user permission bits in the original mode of the file.
But it will throw following error if user is not logged-in.
com.apple.launchd[1]: System: Bug: launchd_core_logic.c:8760 (24498):0
com.apple.launchd[1]: System: job_mig_spawn() can't find its session!
open[24459]: spawn_via_launchd() failed, errno=5 label=[0x0-0x274274].
rootProcess[23127]: LSOpenURLsWithRole() failed with error -10810 for the file /Applications/myApp.app/.
