haiku/docs/user/storage/VolumeRoster.dox

/*
 * Copyright 2002-2014 Haiku, Inc. All rights reserved.
 * Distributed under the terms of the MIT License.
 *
 * Authors:
 *		Vincent Dominguez
 *		John Scipione, jscipione@gmail.com
 *		Ingo Weinhold, bonefish@users.sf.net
 *
 * Corresponds to:
 *		headers/os/storage/VolumeRoster.h	hrev47402
 *		src/kits/storage/VolumeRoster.cpp	hrev47402
 */


/*!
	\file VolumeRoster.h
	\ingroup storage
	\ingroup libbe
	\brief Provides the BVolumeRoster class.
*/


/*!
	\class BVolumeRoster
	\ingroup storage
	\ingroup libbe
	\brief Provides an interface for iterating through available volumes
	       and watching for mounting/unmounting.

	This class wraps the next_dev() function for iterating through the
	list of available volumes and watch_node()/stop_watching() for
	watching volumes.

	\since BeOS R3
*/


/*!
	\fn BVolumeRoster::BVolumeRoster()
	\brief Creates a BVolumeRoster object. The object is ready to be used.

	\since BeOS R3
*/


/*!
	\fn BVolumeRoster::~BVolumeRoster()
	\brief Deletes the volume roster and frees all associated resources.

	If a watch was activated (by StartWatching()), it is deactivated.

	\since BeOS R3
*/



/*!
	\fn status_t BVolumeRoster::GetNextVolume(BVolume *volume)
	\brief Fills out the passed in BVolume object with the next available
	       volume.

	\param volume A pointer to a pre-allocated BVolume object to be
	       initialized to the next available volume.

	\return A status code.
	\retval B_OK Everything went fine.
	\retval B_BAD_VALUE The last volume in the list was already returned.

	\since BeOS R3
*/


/*!
	\fn void BVolumeRoster::Rewind()
	\brief Rewinds the list of available volumes back to the first item.

	The next call to GetNextVolume() will return the first available volume.

	\since BeOS R3
*/


/*!
	\fn status_t BVolumeRoster::GetBootVolume(BVolume *volume)
	\brief Fills out the passed in BVolume object with the boot volume.

	Currently, this method looks for the volume that is mounted at "/boot".
	The only way to fool the system into thinking that there is not a boot
	volume is to rename "/boot" -- but, please refrain from doing this.

	\param volume A pointer to a pre-allocated BVolume to be initialized to
	       refer to the boot volume.

	\return A status code, \c B_OK if everything went fine or an error code
	        otherwise.

	\since BeOS R3
*/


/*!
	\fn status_t BVolumeRoster::StartWatching(BMessenger messenger)
	\brief Starts watching the available volumes for changes.

	Notifications are sent to the specified target whenever a volume is
	mounted or unmounted. The format of the notification messages is
	described under watch_node(). Actually BVolumeRoster just provides a
	more convenient interface for it.

	If StartWatching() has been called before with another target and no
	StopWatching() since, StopWatching() is called first, so that the former
	target won't receive any notifications anymore.

	When the object is destroyed all watching ends as well.

	\param messenger The target which the notification messages are sent.

	\return A status code.
	\retval B_OK Everything went fine.
	\retval B_BAD_VALUE The supplied BMessenger was invalid.
	\retval B_NO_MEMORY There was insufficient memory to carry out this
	        operation.

	\see watch_node()

	\since BeOS R3
*/


/*!
	\fn void BVolumeRoster::StopWatching()
	\brief Stops watching volumes initiated by StartWatching().

	\see stop_watching()

	\since BeOS R3
*/


/*!
	\fn BMessenger BVolumeRoster::Messenger() const
	\brief Returns the messenger currently watching the volume list.

	\return A messenger to the target currently watching the volume list, or
	        an invalid messenger if not watching.

	\since BeOS R3
*/