iokit/IOKit/IOService.h

517     @discussion IOService calls this method in its subclasses in response to the @link open open@/link method, so the subclass may implement the request. The default implementation provides single owner access to an IOService object via <code>open</code>. The object is locked via @link lockForArbitration lockForArbitration@/link before <code>handleOpen</code> is called.
528     @discussion IOService calls this method in its subclasses in response to the @link close close@/link method, so the subclass may implement the request. The default implementation provides single owner access to an IOService object via @link open open@/link. The object is locked via @link lockForArbitration lockForArbitration@/link before <code>handleClose</code> is called.
537     @discussion IOService calls this method in its subclasses in response to the @link open open@/link method, so the subclass may implement the request. The default implementation provides single owner access to an IOService object via @link open open@/link. The object is locked via @link lockForArbitration lockForArbitration@/link before <code>handleIsOpen</code> is called.
565 /*! @function lockForArbitration
567     @discussion The registration, termination and open / close functions of IOService use <code>lockForArbtration</code> to single-thread access to an IOService object. <code>lockForArbitration</code> grants recursive access to the same thread.
570     virtual bool lockForArbitration( bool isSuccessRequired = true );
573     @abstract Unlocks an IOService obkect after a successful @link lockForArbitration lockForArbitration@/link.
905     @discussion For those few IOService objects that obtain service from multiple providers, this method supplies an iterator over a client's providers, locking each in turn with @link lockForArbitration lockForArbitration@/link and returning those that have been opened by the client.
906     @result An iterator over the providers the client has open, or zero if there is a resource failure. The iterator must be released when the iteration is finished. All objects returned by the iteration are retained while the iterator is valid, and the current entry in the iteration is locked with <code>lockForArbitration</code>, protecting it from state changes. */
926     @discussion For IOService objects that may have multiple clients, this method supplies an iterator over a provider's clients, locking each in turn with @link lockForArbitration lockForArbitration@/link and returning those that have opened the provider.
927     @result An iterator over the clients that have opened the provider, or zero if there is a resource failure. The iterator must be released when the iteration is finished. All objects returned by the iteration are retained while the iterator is valid, and the current entry in the iteration is locked with <code>lockForArbitration</code>, protecting it from state changes. */