Disk Utility has a nifty little button to Verify Disk Permissions and another to Repair Disk Permissions. Many use this frequently over the course of basic Mac OS X troubleshooting. The underlying functionality is also exposed at the command line. Diskutil (located in /usr/sbin) has the verifyPermissions and repairPermissions, which roughly correspond to the buttons in Disk Utility. Because these can be run against different disks, each will need the volume indicated following the verb. For example, to run a Verify Disk Permissions against a volume called Seldon, you would use the following command: diskutil verifyPermissions /Volumes/Seldon To then run a Repair Disk Permissions on that same volume, you would…