site_archiver@lists.apple.com Delivered-To: darwin-dev@lists.apple.com - Kevin On Jun 8, 2006, at 10:56 PM, Ryan McGann wrote: Thanks, Ryan _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.appl... I'm responding off the top of my head, so I could be wrong, but I believe your analysis is correct and the Carbon File Manager does rely on coreservicesd to some extent, and the Security.framework relies on securityd as well. In the "launchd model" you should not have to specify a dependency. (The fact that a daemon is consulted is really and implementation detail of the API you're calling.) These APIs should be making blocking calls to the daemons in question--and launchd should launch the daemons when the calls are made. The fact that this isn't happening is a bug in the system, not in your code. I can imagine a few possible explanations (but this is pure speculation): * launchtl might be somewhat non-deterministic in how plists are loaded. If at times your plist is loaded before the coreservicesd or securityd plist, then the lookups for those services will fail, which causes the API to return an error rather than block. * coreservicesd or securityd might not be properly servicing requests before they're fully initialized. They should not service requests until they've initialized themselves, but perhaps they're dequeuing a message they can't handle yet and returning an error. It would help tremendously if you could file a bug <http:// developer.apple.com/bugreporter/>. Distilling it into a small test case, or at least describing the specific API calls you're making, will help us diagnose the problem. Now that the launchd discussion has died down, I guess it's time to kick up the ashes with an honest question. We are using launchd in Tiger to startup our daemon. It is currently not load-on-demand, so it gets launched very early. It's usually process ID 18-25. We seem to be experiencing some problems in Tiger related to how early we get started. In particular, the following APIs seem to rely on daemons to perform their dirty work, but those daemons are not ready when we use them: - The Carbon Alias Manager which is used to determine the location of some files saved in the preferences accessed by our daemon. Sometimes the Alias Manager fails to resolve the aliases, even though they point to files that have not changed. We are using FSResolveAliasNoUI to resolve the alias in our daemon. - The cdsa wrapper libCdsa, which fails sometimes in cdsaCspAttach Both of these issues are reliably unreliable, in that they happen every 1 out of 5 reboots or so. It took quite a bit of time to narrow things down, but by adding a LOT of syslog statements, we found that these two APIs randomly fail. Looking at the syslog and process list in ps, I see that coreservicesd is launched very soon after our daemon, so I am guessing that the Carbon File Manager uses coreservicesd. I am *guessing* that the Security framework uses securityd. Since launchd has no dependancy list, how can I tell launchd that we need these daemons launched *and ready* when our daemon loads? For now, I've hacked around these issues by doing a very kluddy for loop: for ( int i = 0; i < 5; i++ ) { // Call Alia Manager needlessly // Call cdsaCspAttach uneedlessly } But this seems just as error prone, since as machines get faster we might need to change the loop to 10 iterations, etc. Any suggestions? rmcgann@mac.com This email sent to site_archiver@lists.apple.com