June 2008 - launchd-dev - lists.macosforge.org

SampleD failure with dynamic SockServiceName
by David Anderson 13 Aug '09

13 Aug '09

My intention is have launchd start a daemon on a dynamic port, publish the port number via bonjour, and then connect to this port after determining the port number using CFNetService (Bonjour). Starting from SampleD (and using the included client.pl), I can advertise the service on a hard-coded port via bonjour, lookup the port number using Bonjour Browser, modify client.pl to use this port, and connect using client.pl. The SampleD binary starts correctly in an OnDemand fashion correctly. If I change <key>SockServiceName</key> <string>12345</string> to <key>SockServiceName</key> <string>0</string> then lookup the dynamic port number using Bonjour Browser and configure client.pl to use this port, client.pl will NOT connect to this port and outputs this error: connect: Connection refused at ./client.pl line 77. With a dynamic port, I am unable to connect to this port using a modified client.pl. I can find no evidence that the SampleD binary is starting in an OnDemand fashion. Adding <key>OnDemand</key> <false/> has no effect. Is there anything different about the default configuration of a dynamic port vs a hard-coded port that would impeded the ability to connect to the dynamically assigned port? Thanks, Dave

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Re: [launchd-dev] launchd and watchpath
by Don Montalvo 18 Jul '08

18 Jul '08

Of course I meant "Instead of ACL's" -Don Date: Sun, 08 Jun 2008 10:07:33 -0400 > From: Don Montalvo <donmontalvo(a)mac.com> > Subject: [launchd-dev] launchd and watchpath > To: launchd-dev(a)lists.macosforge.org > Message-ID: <41D7B3A5-6EAC-4647-8ACB-D2378ABD170C(a)mac.com> > Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes > > We would like to set up a folder on our Macs that forces incoming > files/folders to inherit permissions. Instead of ADL's, we'd like to > use launchd (and watchpath). I'm not familiar with launchd, so I think > this would be a good way to get my feet wet. > > The shared folder would be: > > /Users/Shared/WORK > > Each user would have an alias to it on their Desktop (created via > logout hook): > > ~/Desktop/WORK > > How can I set up launchd to watch this folder and ensure the contents > are always set to 777? I don't have experience with launchd. I toyed > with it in early Tiger days but there were issues with user launchd so > I gave it up and stuck with cron. I understand launchd works as > advertised on Leopard. Hoping it can help with this little project. :) > > Thanks, > Don

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OnDemand USB Software
by Mike Fischer 11 Jul '08

11 Jul '08

Hi! I'm trying to evaluate if it is feasable to have an on-demand daemon depend on the presence of a certain usb device. I.e. I'd like the daemon to launch when the USB-device is plugged in. So far, looking at tn2083 and the man pages, I don't see any way to have a depency on USB or IOKit in general. Am I missing something here? If there is no direct support would it make sense to have a very small, lightweight daemon always running that registers for IOKit IOServiceAddMatchingNotification notifications and creates a semaphore file that can be used to trigger the launch of the real daemon for example? BTW: This would be mainly for Leopard, although Tiger would be interesting too. Thanks! Mike -- Mike Fischer Softwareentwicklung, EDV-Beratung Schulung, Vertrieb Web: <http://homepage.mac.com/mike_fischer/index.html> Note: I read this list in digest mode! Send me a private copy for faster responses.

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automatic job removal
by John Maisey 26 Jun '08

26 Jun '08

Hi, I have an application that as part of its activation installs a launch agent in the current users ~/Library/LaunchAgents/. The launch agent watches a folder path and when required launches the UNIX command open to locate and launch a background application within the original application package. This all seems to be working fine. If a user chooses to stop using the application they are asked to deactivate it by opening it and pressing a 'deactivate' button. The main reason for this is to deactivate the associated launchd job. However some users of the app. are deleting the application package without doing this. This leaves the user with an orphaned launchd job calling 'open' to find an application that is not on the user's system. Open returns an error and the launchd job returns 'code 1'. This will repeat on a regular basis. I am looking for advice as to how best avoid this eventuality. My initial thought was to host the launchd.plist inside the application package and soft link to it. This won't help because the WatchPath is inside the users account. I tried using a tilde to replace the user's folder path in the WatchPath, but evidently this does not get expanded by launchd. Another option could be to create a plist per user within the application package and soft link to it from ~/Library/LaunchAgents/. This doesn't seem like much of a solution to me. Can you suggest a better solution? Is there a reason for launchd not to expand tilde on launch agent paths? Thanks for your time. John (I am reading in digest mode, so please cc my email address)

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Launch on demand from kernel extension?
by Colin 25 Jun '08

25 Jun '08

Hello, I have an OS X kernel extension that has settings that need to be saved and restored (the settings are not per-user). Since a kernel extension cannot read/write a preference file, I have a helper daemon that interfaces with my kext and handles the reading/writing of the preference file. I have recently converted over from using StartupItems to using launchd to launch my helper daemon at startup. Is it possible, using launchd, to have my kernel extension launch the helper daemon on demand? If so, what is the best way to implement this? I need to support OS X 10.4.11 and above. cheers, colin

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Agent terminating & Fast User Switching
by Peter Alshuth 24 Jun '08

24 Jun '08

Hi all, I have an agent running for each user session that gets launched when the user logs in and will be terminated on a logout. In order to have the background agent running even if the user quits it I use the key to KeepAlive (I check the reason for the quit event and return 0 or 1). Everything works fine when only one user is logged in and out. But when I log out from a fast user switching it will be restarted: He agent fist received the quit event and will terminate by calling exit(1) at the very end. Unfortunately, it will be relaunched during the user logout and the process will immediately receive SIGTERM signal that I also response to. <plist version="1.0"> <dict> <key>KeepAlive</key> <dict> <key>SuccessfulExit</key> <true/> </dict> <key>Label</key> <string>com.mycompany.myAgent</string> <key>OnDemand</key> <false/> <key>ProgramArguments</key> <array> <string>/usr/local/MyStuff/MyAgent.app/Contents/MacOS/ MyAgent</string> </array> <key>RunAtLoad</key> <true/> </dict> </plist> Is there anything I am missing or doing wrong? Thanks for any help, Peter

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launchd and watchpath
by Don Montalvo 08 Jun '08

08 Jun '08

We would like to set up a folder on our Macs that forces incoming files/folders to inherit permissions. Instead of ADL's, we'd like to use launchd (and watchpath). I'm not familiar with launchd, so I think this would be a good way to get my feet wet. The shared folder would be: /Users/Shared/WORK Each user would have an alias to it on their Desktop (created via logout hook): ~/Desktop/WORK How can I set up launchd to watch this folder and ensure the contents are always set to 777? I don't have experience with launchd. I toyed with it in early Tiger days but there were issues with user launchd so I gave it up and stuck with cron. I understand launchd works as advertised on Leopard. Hoping it can help with this little project. :) Thanks, Don

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Re: [launchd-dev] Wiki
by Ian Eiloart 06 Jun '08

06 Jun '08

--On 5 June 2008 10:49:56 -0700 Dave Zarzycki <zarzycki(a)apple.com> wrote: > Ian, > > I don't know about wiki access, but if you propose some changes for the > 'man' page, I'd consider incorporating them. > > davez > Hmm, OK. So, would you consider adding this to the man page: Define kern.hostname in /etc/sysctl.conf if you need a process to load at boot time. Is there any official documentation other than the man page? I'd like to document much more than is appropriate for a man page - more examples, more use cases, etc. -- Ian Eiloart IT Services, University of Sussex x3148

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Re: [launchd-dev] LimitLoadToHosts doesn't work with RunAtLoad
by Ian Eiloart 06 Jun '08

06 Jun '08

--On 5 June 2008 10:49:14 -0700 Dave Zarzycki <zarzycki(a)apple.com> wrote: > > Ian, > > Does adding "kern.hostname=snow.uscs.susx.ac.uk" to /etc/sysctl.conf fix > this behavior? > > davez Yes, it does. Thanks! I still have to maintain a file for each host, but I guess I've achieved what I wanted - a common set of files for automatic configuration based on host identification. -- Ian Eiloart IT Services, University of Sussex x3148

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Wiki
by Ian Eiloart 05 Jun '08

05 Jun '08

Hi, Is it possible to get write access to the wiki? I'd like to put some documentation up there - mainly to expand on what's in the launchd.plist man file. -- Ian Eiloart IT Services, University of Sussex x3148

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