When you want software to run automatically each time you Mac starts up, there are several ways of doing that. Here’s your choice.
launchd
Scheduling background activities like making backups has moved from cron to launchd, and now to a more complex system. This has reduced the reliability of macOS and made it harder to support.
New release lets you save and re-open activity configurations in simple plist files, and fixes a couple of annoying bugs.
Background activities scheduled by third-party software currently use launchd, and run the risk of affecting the user. Would GCD be a better choice of dispatcher?
An experimental tool to let you schedule background tasks of your own, which are managed by Grand Central Dispatch. First alpha release.
The aim is to be able to run commands at regular intervals using GCD rather than launchd. Here are details of the code and resulting log entries, casting light on how GCD works.
Despite its documentation vanishing, it’s clear that GCD does a lot more than provide an easy way to concurrency for app developers.
Irregular Time Machine backups are one of Sierra’s great mysteries. It now looks as if they might have been fixed in 10.12.4.
Schedule a periodic task as a Launch Agent. How close to the expected time does macOS actually run it?
This command tool can now write just the integer passed to it as a log message. This is ideal for instrumenting scripts and apps for analysis.
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