How to identify a mounted device as removable?

Question

How can I figure out if a mounted device can be unmounted/ejected ?

I tried to get all devices with the help of the NSFileManager.

NSArray *keys = [NSArray arrayWithObjects:NSURLVolumeNameKey, NSURLVolumeURLForRemountingKey, NSURLVolumeIsEjectableKey, NSURLVolumeIsRemovableKey, nil];
NSArray *urls = [[NSFileManager defaultManager] mountedVolumeURLsIncludingResourceValuesForKeys:keys options:0];

for (NSURL *url in urls) 
{
NSError *error;
NSNumber *isRemovable;
NSString *volumeName; 

[url getResourceValue:&isRemovable forKey:NSURLVolumeIsRemovableKey error:&error];
[url getResourceValue:&volumeName forKey:NSURLVolumeNameKey error:&error];

NSLog(@"Standard Device : %@ - Removable: %c", volumeName, [isRemovable boolValue]);

}

But when I iterate through the list, I always get this e.g.:

Standard Device Name: My Book - isEjectable:

FYI, "My Book" is a USB drive.

I hope someone can point out what is wrong.

Thanks

Answer 1

You want the NSURLVolumeIsEjectableKey not NSURLVolumeIsRemovableKey.

NSURLVolumeIsRemovableKey means the media can be physically removed from the device. NSURLVolumeIsEjectableKey indicates that the volume can be unmounted.