What are "Disk Permissions" ?

I have a MacPro (and a MacBook). When I was having a problem with something earlier in the week I called Apple Care, and, among other things, I was instructed to click the "Repair Disk Permissions" in Disk Utility. I was surprised when the operation took almost ten minutes, and it looked like thousands of lines of stuff went scrolling by.
(BTW, I did a "Migration Assitant" from a Mac Mini when I started up this Pro; maybe that had something to do with it?)
I'm new to the MacOS, and still learning my way around the underpinnings (well, the surface of the underpinnings...) so I am not familiar with "Disk Permissions."
So, pray tell: what ARE "Disk Permissions," and what happens when I repair them? What does "Verify Disk Permissions" do?
Any sources you can steer me to, I'll be glad to follow thing links.
Thanks,
--PS

Verify Disk Permissions just checks the disk permissions without fixing them. I always just use Repair Disk Permissions.
"Permissions" on files and folders define who is able to access and modify what on the computer. It's one of the reasons Mac OS X is more secure than Windows, and it protects the typical user from taking action that will damage the overall system.
This article explains what Repair Disk Permissions does.
http://docs.info.apple.com/article.html?artnum=25751
It is a good maintenance step to take about once every month, and after a major update or software installation.

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When I repair disk permissions I get the following:Repairing permissions for "MacIntosh HD" Determining correct file permissions. Permissions differ on ./Library/Widgets, should be drwxr-xr-x , they are drwxrwxr-x Owner and group corrected on ./Library/W

Repairing permissions for “MacIntosh HD”
Determining correct file permissions.
Permissions differ on ./Library/Widgets, should be drwxr-xr-x , they are drwxrwxr-x
Owner and group corrected on ./Library/Widgets
Permissions corrected on ./Library/Widgets
Permissions differ on ./System/Library/User Template, should be drwx------ , they are drwxr-xr-x
Owner and group corrected on ./System/Library/User Template
Permissions corrected on ./System/Library/User Template
Group differs on ./usr/bin/fetchmail, should be 0, group is 6
Permissions differ on ./usr/bin/fetchmail, should be -rwxr-xr-x , they are -rwxr-sr-x
Owner and group corrected on ./usr/bin/fetchmail
Permissions corrected on ./usr/bin/fetchmail
Permissions differ on ./usr/lib/php/build/Makefile.global, should be -r--r--r-- , they are -r-xr-xr-x
Owner and group corrected on ./usr/lib/php/build/Makefile.global
Permissions corrected on ./usr/lib/php/build/Makefile.global
Permissions differ on ./usr/lib/php/build/acinclude.m4, should be -r--r--r-- , they are -r-xr-xr-x
Owner and group corrected on ./usr/lib/php/build/acinclude.m4
Permissions corrected on ./usr/lib/php/build/acinclude.m4
Permissions differ on ./usr/lib/php/build/mkdep.awk, should be -r--r--r-- , they are -r-xr-xr-x
Owner and group corrected on ./usr/lib/php/build/mkdep.awk
Permissions corrected on ./usr/lib/php/build/mkdep.awk
Permissions differ on ./usr/lib/php/build/phpize.m4, should be -r--r--r-- , they are -r-xr-xr-x
Owner and group corrected on ./usr/lib/php/build/phpize.m4
Permissions corrected on ./usr/lib/php/build/phpize.m4
Permissions differ on ./usr/lib/php/build/scan_makefile_in.awk, should be -r--r--r-- , they are -r-xr-xr-x
Owner and group corrected on ./usr/lib/php/build/scan_makefile_in.awk
Permissions corrected on ./usr/lib/php/build/scan_makefile_in.awk
Permissions differ on ./usr/lib/system/libmathCommon.A.dylib, should be -r-xr-xr-x , they are -rwxr-xr-x
Owner and group corrected on ./usr/lib/system/libmathCommon.A.dylib
Permissions corrected on ./usr/lib/system/libmathCommon.A.dylib
Permissions differ on ./usr/libexec/dumpemacs, should be -r-sr-xr-x , they are -r-xr-xr-x
Owner and group corrected on ./usr/libexec/dumpemacs
Permissions corrected on ./usr/libexec/dumpemacs
Permissions repair complete
The privileges have been verified or repaired on the selected volume
Then I sometimes get the brown screen that states,You must re-start your computer.
I have already zeroed out the hard drive and re-installed Panther and the upgrade Tiger disc.
I repair permissions using the Tiger disc upgrade.
Can anyone help me with this??

> I repair permissions using the Tiger disc upgrade.
One thing to note... When running Repair Disk Permissions, it is best to run it while started up normally, from your normal startup disk, not from a Mac OS X installation disc. The only time you should run it while started up from an installation disc is if some problem is preventing you from starting up normally. OTOH, Repair Disk can only be used when starting up from a different disk (such as an installation disc).
So, I would start up normally, run Disk Utility, and use Repair Disk Permissions on your normal startup disk.
NOTE: Repair Disk Permissions often gives alerts messages that can be ignored. They are more "informational," not serious errors.
http://support.apple.com/kb/TS1448
You should still run it periodically. When you run it, what needs to be repaired has been repaired; consider the rest of it an FYI. I've never experience a problem, where a Repair Disk Permissions message actually caused a problem. But, if you ever get an error while running Repair Disk (or Verify Disk), that is usually a serious problem.

My iMac, OS 10.7.5, is abnormally slow on start-up, taking many minutes for my password sign-in window to show up. I've run Disk Permissions and have verified my hard drive and all is in order. What do I do to start up my Mac in a normal manner?

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For example, if the problem is a slow startup taking three minutes, post the messages timestamped within three minutes after the boot time, not before. Please include the BOOT_TIME message at the beginning of the log extract.
If there are runs of repeated messages, post only one example of each. Don’t post many repetitions of the same message.
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Step 2
Still in Console, look under System Diagnostic Reports for crash or panic logs, and post the entire contents of the most recent one, if any. In the interest of privacy, I suggest you edit out the “Anonymous UUID,” a long string of letters, numbers, and dashes in the header of the report, if present (it may not be.) Please don’t post shutdownStall, spin, or hang logs — they're very long and not helpful.

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Well, try this (I was able to fix my with these steps):
Go Utilities > Disk Utility
Select your Startup Disk, e.g. Macintosh HD
Then, under the First Aid Tab, click Verify Disk Permissions.
If there are errors, then click repair Disk Permissions.
After it is done, restart the computer and see if your problem is resolved.
I hope this help.
Zeke
www.ZekeYuen.com/blog/

Repairing Disk Permissions? What's Best?

Hello,
I was wondering if there is a difference in how, and what you use to repair disk permissions.
The reason I ask is, if I use say the latest version of DiskWarrior 1.4.0, reboot my computer, and then run Apple's Disk Utility, it may change the disk permissions all over again.
Which application is doing the right thing?
I always assumed that Disk Utility (From Apple) was the way to go, but I just wanted to see what the general consensus is. (because I know that DiskWarrior is a highly respected program also)
Thanks Again,
Eric

Gulliver,
I am revising my opinion about disk permission repair..
The reason is, I first ran Disk Utility from my hard drive, no repairs needed.
Then I booted from The Disk Warrior 4.0 start up disk and got the disk repairs below.
Then I restarted (which took quite a bit longer than usual) ran Disk Utilities from the hard drive again, it found several repairs necessary. (Also posted, and marked below.
My conclusion is permission repairs should be done on the hard drive, after everything has loaded.
Let me know what you all think,
Thanks,
Eric
Below this point is from DiskWarrior 4.0:
Permissions:
parent directory ./Users/Shared/SC Info does not exist
Started verify/repair permissions on disk disk0s10 SandBox
Determining correct file permissions.
Permissions differ on ./Library/Widgets, should be drwxrwxr-x , they are drwxr-xr-x
Owner and group corrected on ./Library/Widgets
Permissions corrected on ./Library/Widgets
Group differs on ./usr/bin/fetchmail, should be 6, group is 0
Permissions differ on ./usr/bin/fetchmail, should be -rwxr-sr-x , they are -rwxr-xr-x
Owner and group corrected on ./usr/bin/fetchmail
Permissions corrected on ./usr/bin/fetchmail
Permissions differ on ./usr/lib/php/build/Makefile.global, should be -r-xr-xr-x , they are -r--r--r--
Owner and group corrected on ./usr/lib/php/build/Makefile.global
Permissions corrected on ./usr/lib/php/build/Makefile.global
Permissions differ on ./usr/lib/php/build/acinclude.m4, should be -r-xr-xr-x , they are -r--r--r--
Owner and group corrected on ./usr/lib/php/build/acinclude.m4
Permissions corrected on ./usr/lib/php/build/acinclude.m4
Permissions differ on ./usr/lib/php/build/mkdep.awk, should be -r-xr-xr-x , they are -r--r--r--
Owner and group corrected on ./usr/lib/php/build/mkdep.awk
Permissions corrected on ./usr/lib/php/build/mkdep.awk
Permissions differ on ./usr/lib/php/build/phpize.m4, should be -r-xr-xr-x , they are -r--r--r--
Owner and group corrected on ./usr/lib/php/build/phpize.m4
Permissions corrected on ./usr/lib/php/build/phpize.m4
Permissions differ on ./usr/lib/php/build/scanmakefilein.awk, should be -r-xr-xr-x , they are -r--r--r--
Owner and group corrected on ./usr/lib/php/build/scanmakefilein.awk
Permissions corrected on ./usr/lib/php/build/scanmakefilein.awk
Permissions differ on ./usr/lib/system/libmathCommon.A.dylib, should be -rwxr-xr-x , they are -r-xr-xr-x
Owner and group corrected on ./usr/lib/system/libmathCommon.A.dylib
Permissions corrected on ./usr/lib/system/libmathCommon.A.dylib
The privileges have been verified or repaired on the selected volume
Verify/repair finished permissions on disk disk0s10 SandBox
Below this point, is after restarting, and running Disk Utility from Hard Drive:
Repairing permissions for “SandBox”
Determining correct file permissions.
Permissions differ on ./Library/Widgets, should be drwxr-xr-x , they are drwxrwxr-x
Owner and group corrected on ./Library/Widgets
Permissions corrected on ./Library/Widgets
Group differs on ./usr/bin/fetchmail, should be 0, group is 6
Permissions differ on ./usr/bin/fetchmail, should be -rwxr-xr-x , they are -rwxr-sr-x
Owner and group corrected on ./usr/bin/fetchmail
Permissions corrected on ./usr/bin/fetchmail
Permissions differ on ./usr/lib/php/build/Makefile.global, should be -r--r--r-- , they are -r-xr-xr-x
Owner and group corrected on ./usr/lib/php/build/Makefile.global
Permissions corrected on ./usr/lib/php/build/Makefile.global
Permissions differ on ./usr/lib/php/build/acinclude.m4, should be -r--r--r-- , they are -r-xr-xr-x
Owner and group corrected on ./usr/lib/php/build/acinclude.m4
Permissions corrected on ./usr/lib/php/build/acinclude.m4
Permissions differ on ./usr/lib/php/build/mkdep.awk, should be -r--r--r-- , they are -r-xr-xr-x
Owner and group corrected on ./usr/lib/php/build/mkdep.awk
Permissions corrected on ./usr/lib/php/build/mkdep.awk
Permissions differ on ./usr/lib/php/build/phpize.m4, should be -r--r--r-- , they are -r-xr-xr-x
Owner and group corrected on ./usr/lib/php/build/phpize.m4
Permissions corrected on ./usr/lib/php/build/phpize.m4
Permissions differ on ./usr/lib/php/build/scanmakefilein.awk, should be -r--r--r-- , they are -r-xr-xr-x
Owner and group corrected on ./usr/lib/php/build/scanmakefilein.awk
Permissions corrected on ./usr/lib/php/build/scanmakefilein.awk
Permissions differ on ./usr/lib/system/libmathCommon.A.dylib, should be -r-xr-xr-x , they are -rwxr-xr-x
Owner and group corrected on ./usr/lib/system/libmathCommon.A.dylib
Permissions corrected on ./usr/lib/system/libmathCommon.A.dylib
Permissions repair complete
The privileges have been verified or repaired on the selected volume

Disk Permissions are these ok to leave alone?

I just repaired my disk permissions and this is what came up:
Permissions differ on "System/Library/CoreServices/Front Row.app/Contents/CodeResources", should be -rw-r--r-- , they are lrw-r--r-- .
Permissions differ on "System/Library/CoreServices/Front Row.app/Contents/PlugIns/DVD.frappliance/Contents/CodeResources", should be -rw-r--r-- , they are lrw-r--r-- .
Permissions differ on "System/Library/CoreServices/Front Row.app/Contents/PlugIns/FRSettings.frappliance/Contents/CodeResources", should be -rw-r--r-- , they are lrw-r--r-- .
Permissions differ on "System/Library/CoreServices/Front Row.app/Contents/PlugIns/FRSources.frappliance/Contents/CodeResources", should be -rw-r--r-- , they are lrw-r--r-- .
Permissions differ on "System/Library/CoreServices/Front Row.app/Contents/PlugIns/Movies.frappliance/Contents/CodeResources", should be -rw-r--r-- , they are lrw-r--r-- .
Permissions differ on "System/Library/CoreServices/Front Row.app/Contents/PlugIns/Music.frappliance/Contents/CodeResources", should be -rw-r--r-- , they are lrw-r--r-- .
Permissions differ on "System/Library/CoreServices/Front Row.app/Contents/PlugIns/Photos.frappliance/Contents/CodeResources", should be -rw-r--r-- , they are lrw-r--r-- .
Permissions differ on "System/Library/CoreServices/Front Row.app/Contents/PlugIns/Podcasts.frappliance/Contents/CodeResources", should be -rw-r--r-- , they are lrw-r--r-- .
Permissions differ on "System/Library/CoreServices/Front Row.app/Contents/PlugIns/TV.frappliance/Contents/CodeResources", should be -rw-r--r-- , they are lrw-r--r-- .
Permissions differ on "System/Library/PrivateFrameworks/BackRow.framework/Versions/A/CodeResources", should be -rw-r--r-- , they are lrw-r--r-- .
Warning: SUID file "System/Library/Filesystems/AppleShare/afpLoad" has been modified and will not be repaired.
Warning: SUID file "System/Library/PrivateFrameworks/DiskManagement.framework/Versions/A/Resources /DiskManagementTool" has been modified and will not be repaired.
Warning: SUID file "usr/sbin/pppd" has been modified and will not be repaired.
Warning: SUID file "usr/sbin/vpnd" has been modified and will not be repaired.
ACL found but not expected on "Applications/Utilities".
I kind of looked online and i think most of these you can just ignore...is that right? or do i have to do anything on any of these? what do you recommend?
Thanks.

I did mention it in my original post. hehe
I did look at the crash log, but i didnt understand it. When it does it again (and is has been going all day so must be due for a crash in the next few hours), i copy it here. Thanks for helping. hopefully there will be something in the crash log that you can help me to decifer.

What could change the disk permissions?

When I talked to an advisor from Apple Care, he asked me to do "verify disk permissions" under the First Aid tab of the Disk Utility software. These are the various read/write/execute permissions of Unix file systems. To my surprise, there were about 7-8 files' permissoins were changed.
What could change the file permissions? Some of the files are related to Safari which I don't use at all.
The reason I contacted Apple Care is that my Mac Pro lost the sound output after I woke it up from the sleep mode. There was no sound output from iTunes or YouTube vidoes. That is why I contacted AppleCare. After I did a "repair disk permissions", the sound output returns.

You are looking at the report by Disk Utility as it repaired permissions on files based on the permissions database of your OS X installation. If those permissions differ from the file's actual settings, then Disk Utility changes them to conform with the database's permissions.
In most cases the reported information you see in Disk Utility are false positives that result in no real change but just an information message that you can ignore.
In your case it's probable that one of the apps you had open made an improper write to the disk when you put the computer to sleep, and that ended up changing some file permissions that should not have been changed.

Repairing disk permissions daily what is wrong with my macbook pro

repairing disk permissions daily what is wrong with my macbook pro

Thanks Clinton - that is what I was afraid of so I have backed up to another hard drive and I ran that program the results are posted below
Hardware Information:
          MacBook Pro (15-inch, Mid 2010)
          MacBook Pro - model: MacBookPro6,2
          1 2.66 GHz Intel Core i7 CPU: 2 cores
          4 GB RAM
Video Information:
          NVIDIA GeForce GT 330M - VRAM: 512 MB
          Intel HD Graphics - VRAM: 288 MB
System Software:
          Mac OS X 10.6.8 (10K549) - Uptime: 0 days 0:8:24
Disk Information:
          Hitachi HTS545050B9SA02 disk0 : (465.76 GB)
                    (null) (disk0s1) <not mounted>: 200 MB
                    Macintosh HD (disk0s2) /: 434 GB (16.5 GB free)
                    BOOTCAMP (disk0s3) /Volumes/BOOTCAMP: 31.44 GB (2.06 GB free)
          MATSHITADVD-R UJ-898
USB Information:
          Western Digital Ext HDD 1021 1.82 TB
                    (null) (disk1s1) <not mounted>: 200 MB
                    Elements (disk1s2) /Volumes/Elements: 1.82 TB (944.25 GB free)
          Western Digital My Book          465.76 GB
                    (null) (disk2s1) <not mounted>: 200 MB
                    Time Machine Backups (disk2s2) /Volumes/Time Machine Backups: 465.44 GB (32.37 GB free)
          EPSON EPSON Scanner
          Apple Inc. Apple Internal Keyboard / Trackpad
          Apple Inc. BRCM2070 Hub
                    Apple Inc. Bluetooth USB Host Controller
          Apple Internal Memory Card Reader
          Microsoft Compact Optical Mouse 500
          Apple Computer, Inc. IR Receiver
          Apple Inc. Built-in iSight
FireWire Information:
Thunderbolt Information:
Kernel Extensions:
Problem System Launch Daemons:
          [not loaded] org.samba.winbindd.plist
Problem System Launch Agents:
          [failed] com.apple.Kerberos.renew.plist
Launch Daemons:
          [loaded] com.adobe.fpsaud.plist
          [loaded] com.adobe.SwitchBoard.plist
          [loaded] com.smithmicro.schedulerdaemon.plist
Launch Agents:
          [not loaded] com.adobe.AAM.Updater-1.0.plist
          [loaded] com.adobe.CS5ServiceManager.plist
User Launch Agents:
          [loaded] com.adobe.AAM.Updater-1.0.plist
          [loaded] com.adobe.ARM.930da3ce175de4e82bd3cdf1dd8571f74bd3b6a7236bc94bfc00f6e9.plist
          [failed] com.apple.CSConfigDotMacCert-[redacted]@me.com-SharedServices.Agent.plist
          [loaded] com.google.keystone.agent.plist
          [not loaded] com.smithmicro.cleaning.schedulermailer.plist
User Login Items:
          iTunesHelper
          EEventManager
          FontAgent Activator
          Aimersoft Helper Compact
3rd Party Preference Panes:
          Flash Player
          Flip4Mac WMV
          FAPPreferences
          Growl
Internet Plug-ins:
          AdobeAAMDetect.plugin
          AdobePDFViewer.plugin
          Flash Player.plugin
          FlashPlayer-10.6.plugin
          Flip4Mac WMV Plugin.plugin
          Google Earth Web Plug-in.plugin
          iPhotoPhotocast.plugin
          JavaAppletPlugin.plugin
          NPRoblox.plugin
          QuickTime Plugin.plugin
          Silverlight.plugin
          Unity Web Player.plugin
User Internet Plug-ins:
Bad Fonts:
          None
Top Processes by CPU:
               5%          EtreCheck
               3%          syslogd
               2%          WindowServer
               1%          fontd
               0%          LaunchCFMApp
               0%          EPSON Scanner
               0%          ODSAgent
Top Processes by Memory:
          102 MB mds
          53 MB    WindowServer
          53 MB    Mail
          37 MB    Finder
          20 MB    coreservicesd
          20 MB    FontAgent Activator
          20 MB    EtreCheck
          16 MB    Dock
          16 MB    mdworker
          12 MB    Aimersoft Helper Compact
Virtual Memory Statistics
          2.26 GB Free RAM
          531 MB Active RAM
          420 MB Inactive RAM
          702 MB Wired RAM
          284 MB Page-ins
          0 B      Page-outs

What are the best practices to replace a disk in 6140 ?

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What are the different ways to back up your photos from iphoto using a MacBook Pro which does not have a disk drive?

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LN

I recently repaired disk permissions on my mac HD and now my on-board speakers wont work, the icon is greyed out and only works when my headphones are plugged in.

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Hi . i have Intel based iMac. i erased whole hard disk. now it flashes folder icon with question mark... i have no internet or orginal dvd.... i want to clean install any mac osx..friend got mac book pro and osx in dmg format . what are my options?

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What are "Disk Permissions" ?

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