Thanks Ronni for your very clear explanation. Cheers, Michael Sent from my iPhone
> On 4 Oct 2015, at 11:15 AM, Ronni Brown <ro...@mac.com> wrote: > > Hi Michael and any member interested in this subject, > > Michael’s previous questions to the list under the Subject: Re: the spinning > beach ball has changed! > >> "Going by how often running "repair permissions" seemed to work for me, does >> this mean (a) I was deluded (b) Apple has sorted something out that had >> lingered for a long time or (c) software updates are going to be released >> every three weeks or so 😇?" > > > To answer your question, I’ll need to explain to you what “Repair > Permissions” using Disk Utility in OS X prior to El Capitan repaired. > Hopefully below will help answer your previous questions. > > Repair Permissions in Disk Utility - Reset Home Folder Permissions in > Terminal > > Part A of my Reply: > Repair Permissions in Disk Utility in OS X prior to El Capitan > > In OS X, each file contains information specifying which users (or parts of > the system) can read it, modify it, or execute it. > This information is collectively known as permissions. If a file has > incorrect permissions, it can cause apps to misbehave in various ways, such > as crashing or failing to launch. > > Ordinarily, installers set the correct permissions for the files they > install, and the permissions stay that way permanently. However, a poorly > written installer can mess up permissions — even for files it did not install > — and if you use Unix commands such as chown and chmod, you can accidentally > set files’ permissions incorrectly. > These sorts of problems occur infrequently, but they do occur. > > The Repair Permissions feature looks for certain software installed using > Apple’s installer, which saves files called receipts that list the locations > and initial permissions of all the files in a given package. Repair > Permissions compares the current permissions to those in the receipts and, if > it finds any differences, changes the files back. > The command ignores software installed in other ways (using a different > installer or drag-and-drop installation, for instance) and knows nothing > about permission changes you may have made deliberately. > > Permissions don’t go out of whack all by themselves; you (or software you > install) must do something to change them. > > Are all files affected by Repair Disk Permissions? > > No. As you may have inferred from the above description, only those files > installed using OS X’s Installer utility and whose installation packages > leave behind a proper receipt in /Library/Receipts are affected by the Repair > Disk Permissions function. > > This means that most of the files affected by the Repair Disk Permissions > function are system-level files, application files, or system add-ons—not > applications installed by drag-and-drop, and not your documents or other > user-level files. > Repairing permissions is mainly a tool for fixing 'permissions-related' > problems with OS-level Apple software . > But beyond that, only certain receipts are referenced, all of them associated > with OS-X-related software. > > Although some might argue that restricting the Repair Disk Permissions > function to Apple-installed software is a limitation, it’s also good > security. If third-party receipts were used as references when repairing > permissions, a piece of malware could leave behind a receipt designed to > maliciously change permissions on system-level files—for example, to assign > more-accessible permissions on normally secure files and directories. This > could be a major security risk. > > But starting in OS X 10.11 El Capitan, the Repair Permissions feature is gone > from Disk Utility entirely. > Beginning with OS X El Capitan, system file permissions are automatically > protected. > It's no longer necessary to verify or repair permissions with Disk Utility. > Instead, permissions are repaired automatically when you install software > using Apple’s installer. > — > Part B of my Reply: > Does repairing permissions affect third-party application files? > > Apple’s description of the Repair Disk Permissions function seems to imply > that any software, including third-party software, installed using Installer > and accompanied by a receipt in /Library/Receipts is affected by repairing > permissions. > However, we know from my previous reply above that this isn’t the case. The > only third-party software affected by repairing permissions is software > included with Mac OS X and installed by the Mac OS X Installer. > > Reset Home Folder Permissions in Terminal > > Disk Utility only checks a limited subset of files, and it won’t repair > anything within your Home folder. There is a slightly more convoluted way to > fix permissions issues there. > Why might you want to do this, you ask? The most common scenario is that > something’s gone wonky with files or folders in your Home folder; you try to > save something to your Desktop, say, and your Mac tells you that you don’t > have permission to do so. > > Reset ‘Home Folder Permissions’ in Mountain Lion & Mavericks & Yosemite > > You can reset your Home Folder Permissions from the Recovery HD using the > Reset Password application. > This utility was primarily designed to reset user passwords; nonetheless, > this tool also has the ability to Reset a User’s home folder permissions and > ACL’s. Keep in mind that this process resets ALL home folder permissions, > including intentionally changed permissions that may have benefited the user. > > Again, the Reset Password application is ONLY available from an OS X Recovery > system. > > Once running from OS X Recovery, you must open Terminal application (via the > Utilities menu), type resetpassword and press Return. > Once Reset Password opens, simply select the system volume and the user > account you want to reset and click ‘Reset’. > NOTE: You do NOT have to enter a New Password > > INSTRUCTIONS: > 1. Shut Down your computer > 2. Boot to the Recovery HD: Start the computer and after the chime press and > hold down the COMMAND and R keys until the menu screen appears. > Alternatively, start the computer and after the chime press and hold down the > OPTION key until the boot manager screen appears. > Select the Recovery HD and click on the downward pointing arrow button. > > 3. OpenTerminal application (via the Utilities menu). > 4. type resetpassword and press return > 5. Once Reset Password opens > Select your Hard Disk volume > Select your user account (the account you want to Reset) > Click the button to ‘Reset Home folder permissions and ACLs’ > 6. And Click ‘Reset’ > > NOTE: DO NOT enter a New user password - leave all that blank > > The reset process takes just a couple of minutes. > When it’s done, exit the programs you’ve opened and restart your Mac. > > Cheers, > Ronni > > 13-inch MacBook Air (April 2014) > 1.7GHz Dual-Core Intel Core i7, Turbo Boost to 3.3GHz > 8GB 1600MHz LPDDR3 SDRAM > 512GB PCIe-based Flash Storage > > OS X Yosemite 10.10.2 > > -- The WA Macintosh User Group Mailing List -- > Archives - <http://www.wamug.org.au/mailinglist/archives.shtml> > Guidelines - <http://www.wamug.org.au/mailinglist/guidelines.shtml> > Settings & Unsubscribe - > <http://lists.wamug.org.au/listinfo/wamug.org.au-wamug>
-- The WA Macintosh User Group Mailing List -- Archives - <http://www.wamug.org.au/mailinglist/archives.shtml> Guidelines - <http://www.wamug.org.au/mailinglist/guidelines.shtml> Settings & Unsubscribe - <http://lists.wamug.org.au/listinfo/wamug.org.au-wamug>