Provides the ability to read and write the data of a file. More...

Inherits BNode, and BPositionIO.

Public Member Functions
	BFile ()
	Creates an uninitialized BFile object.

	BFile (const BDirectory dir, const char path, uint32 openMode)
	Creates a BFile and initializes it to the file referred to by the supplied path name relative to the specified BDirectory and according to the specified open mode.

	BFile (const BEntry *entry, uint32 openMode)
	Creates a BFile and initializes it to the file referred to by the supplied BEntry and according to the specified open mode.

	BFile (const BFile &file)
	Creates a copy of the supplied BFile.

	BFile (const char *path, uint32 openMode)
	Creates a BFile and initializes it to the file referred to by the supplied path name and according to the specified open mode.

	BFile (const entry_ref *ref, uint32 openMode)
	Creates a BFile and initializes it to the file referred to by the supplied entry_ref and according to the specified open mode.

virtual	~BFile ()
	Destroys the BFile object and frees all allocated resources.

virtual status_t	GetSize (off_t *size) const
	Gets the size of the file.

bool	IsReadable () const
	Reports whether or not the file is readable.

bool	IsWritable () const
	Reports whether or not the file is writable.

BFile &	operator= (const BFile &file)
	Assigns another BFile to this BFile.

virtual off_t	Position () const
	Gets the current read/write position within the file.

virtual ssize_t	Read (void *buffer, size_t size)
	Reads a number of bytes from the file into a buffer.

virtual ssize_t	ReadAt (off_t location, void *buffer, size_t size)
	Reads a number of bytes from a certain position within the file into a buffer.

virtual off_t	Seek (off_t offset, uint32 seekMode)
	Seeks to another read/write position within the file.

virtual status_t	SetSize (off_t size)
	Sets the size of the file.

status_t	SetTo (const BDirectory dir, const char path, uint32 openMode)
	Re-initializes the BFile to the file referred to by the supplied path name relative to the specified BDirectory and according to the specified open mode.

status_t	SetTo (const BEntry *entry, uint32 openMode)
	Re-initializes the BFile to the file referred to by the supplied BEntry and according to the specified open mode.

status_t	SetTo (const char *path, uint32 openMode)
	Re-initializes the BFile to the file referred to by the supplied path name and according to the specified open mode.

status_t	SetTo (const entry_ref *ref, uint32 openMode)
	Re-initializes the BFile to the file referred to by the supplied entry_ref and according to the specified open mode.

virtual ssize_t	Write (const void *buffer, size_t size)
	Writes a number of bytes from a buffer into the file.

virtual ssize_t	WriteAt (off_t location, const void *buffer, size_t size)
	Writes a number of bytes from a buffer at a certain position into the file.

Public Member Functions inherited from BNode
	BNode ()
	Creates an uninitialized BNode object.

	BNode (const BDirectory dir, const char path)
	Creates a BNode object and initializes it to the entry referred to by the specified path rooted in the specified directory.

	BNode (const BEntry *entry)
	Creates a BNode object and initializes it to the specified filesystem entry.

	BNode (const BNode &node)
	Creates a copy of the given BNode.

	BNode (const char *path)
	Creates a BNode object and initializes it to the entry referred to by the specified path.

	BNode (const entry_ref *ref)
	Creates a BNode object and initializes it to the specified entry_ref.

virtual	~BNode ()
	Frees all resources associated with the BNode.

int	Dup ()
	Gets the POSIX file descriptor referred to by this node.

virtual status_t	GetStat (struct stat *st) const
	Fills in the given stat structure with the `stat()` information for this object.

status_t	InitCheck () const
	Checks whether the object has been properly initialized or not.

status_t	SetTo (const entry_ref *ref)
	Initializes the object to the specified entry_ref.

status_t	SetTo (const BEntry *entry)
	Initializes the object to the specified filesystem entry.

status_t	SetTo (const char *path)
	Initializes the object to the specified path.

status_t	SetTo (const BDirectory dir, const char path)
	Initializes the object to the entry referred by the specified path relative to the the specified directory.

void	Unset ()
	Returns the object to an uninitialized state.

status_t	Lock ()
	Attains an exclusive lock on the data referred to by this node so that it may not be modified by any other objects or methods.

status_t	Unlock ()
	Unlocks the date referred to by this node.

status_t	Sync ()
	Immediately performs any pending disk actions on the node.

ssize_t	WriteAttr (const char name, type_code type, off_t offset, const void buffer, size_t length)
	Writes data from a buffer to an attribute.

ssize_t	ReadAttr (const char name, type_code type, off_t offset, void buffer, size_t length) const
	Reads data from an attribute into buffer.

status_t	RemoveAttr (const char *name)
	Deletes the attribute given by name.

status_t	RenameAttr (const char oldName, const char newName)
	Moves the attribute given by oldName to newName.

status_t	GetAttrInfo (const char name, struct attr_info info) const
	Fills in the pre-allocated attr_info struct pointed to by info with information about the attribute specified by name.

status_t	GetNextAttrName (char *buffer)
	Copies the name of the attribute into `buffer` and then advances the pointer to the next attribute.

status_t	RewindAttrs ()
	Resets the object's attribute pointer to the first attribute in the list.

status_t	WriteAttrString (const char name, const BString data)
	Writes the specified string to the specified attribute, clobbering any previous data.

status_t	ReadAttrString (const char name, BString result) const
	Reads the data of the specified attribute into the pre-allocated result.

BNode &	operator= (const BNode &node)
	Initializes the object as a copy of other.

bool	operator== (const BNode &node) const
	Tests whether this and the supplied BNode object are equal.

bool	operator!= (const BNode &node) const
	Tests whether this and the supplied BNode object are not equal.

Public Member Functions inherited from BStatable
status_t	GetAccessTime (time_t *atime) const
	Fills out atime with the access time of the node.

status_t	GetCreationTime (time_t *ctime) const
	Fills out ctime with the creation time of the node.

status_t	GetGroup (gid_t *group) const
	Fills out the node's GID into group.

status_t	GetModificationTime (time_t *mtime) const
	Fills out mtime with the last modification time of the node.

status_t	GetNodeRef (node_ref *ref) const
	Fills out ref with the `node_ref` of the node.

status_t	GetOwner (uid_t *owner) const
	Fills out the node's UID into owner.

status_t	GetPermissions (mode_t *permissions) const
	Fills out perms with the permissions of the node.

status_t	GetSize (off_t *size) const
	Fills out the size of the node's data (not counting attributes) into size.

virtual status_t	GetStat (struct stat *stat) const =0
	Fills out the stat structure for the node.

status_t	GetVolume (BVolume *volume) const
	Fills out vol with the the volume that the node lives on.

bool	IsDirectory () const
	Returns whether or not the node is a directory.

bool	IsFile () const
	Returns whether or not the node is a file.

bool	IsSymLink () const
	Returns whether or not the node is a symbolic link.

status_t	SetAccessTime (time_t atime)
	Sets the node's access time to atime.

status_t	SetCreationTime (time_t ctime)
	Sets the node's creation time to ctime.

status_t	SetGroup (gid_t group)
	Sets the node's GID to group.

status_t	SetModificationTime (time_t mtime)
	Sets the node's last modification time to mtime.

status_t	SetOwner (uid_t owner)
	Sets the node's UID to owner.

status_t	SetPermissions (mode_t permissions)
	Sets the node's permissions to perms.

Public Member Functions inherited from BPositionIO
	BPositionIO ()
	This constructor does nothing.

virtual	~BPositionIO ()
	This destructor does nothing.

virtual status_t	GetSize (off_t *size) const
	Get the size of the object or data.

virtual off_t	Position () const =0
	Pure virtual to return the current position of the cursor.

virtual ssize_t	Read (void *buffer, size_t size)
	Read data from current position.

virtual ssize_t	ReadAt (off_t position, void *buffer, size_t size)=0
	Pure virtual to read data from a certain position.

status_t	ReadAtExactly (off_t position, void buffer, size_t size, size_t _bytesRead=NULL)
	Reads an exact amount of data from the object at the specified position into a buffer.

virtual off_t	Seek (off_t position, uint32 seekMode)=0
	Pure virtual to move the cursor to a certain position.

virtual status_t	SetSize (off_t size)
	Set the size of the object or data.

virtual ssize_t	Write (const void *buffer, size_t size)
	Write data to the current position.

virtual ssize_t	WriteAt (off_t position, const void *buffer, size_t size)=0
	Pure virtual to write data to a certain position.

status_t	WriteAtExactly (off_t position, const void buffer, size_t size, size_t _bytesWritten=NULL)
	Writes an exact amount of data from a buffer to the object at the specified position.

Public Member Functions inherited from BDataIO
	BDataIO ()
	This constructor does nothing.

virtual	~BDataIO ()
	This destructor does nothing.

virtual status_t	Flush ()
	Writes pending data to underlying storage.

virtual ssize_t	Read (void *buffer, size_t size)
	Reads data from the object into a buffer.

status_t	ReadExactly (void buffer, size_t size, size_t _bytesRead=NULL)
	Reads an exact amount of data from the object into a buffer.

virtual ssize_t	Write (const void *buffer, size_t size)
	Writes data from a buffer to the object.

status_t	WriteExactly (const void buffer, size_t size, size_t _bytesWritten=NULL)
	Writes an exact amount of data from a buffer to the object.

Detailed Description

Provides the ability to read and write the data of a file.

The file is automatically opened when you initialize a BFile and is automatically closed when you re-initialize or destroy the object.

Symbolic links are automatically transversed by opening a BFile. The node that the BFile ends up opening will be the file or directory that the link points to, not the symbolic link file itself.

Since: BeOS R3

Constructor & Destructor Documentation

◆ BFile() [1/6]

BFile::BFile ( )

Creates an uninitialized BFile object.

Should be followed by a call to one of the SetTo() methods, or an assignment:

Since: BeOS R3

◆ BFile() [2/6]

BFile::BFile ( const BFile & file )

Creates a copy of the supplied BFile.

If file is uninitialized, the newly constructed BFile will be too.

Parameters

file	The BFile object to be copied.

Since: BeOS R3

◆ BFile() [3/6]

BFile::BFile	(	const entry_ref *	ref,
		uint32	openMode
	)

Creates a BFile and initializes it to the file referred to by the supplied entry_ref and according to the specified open mode.

Parameters

ref	The entry_ref referring to the file.
openMode	The mode in which the file should be opened.

See also: SetTo(const entry_ref* ref, uint32 openMode)

Since: BeOS R3

◆ BFile() [4/6]

BFile::BFile	(	const BEntry *	entry,
		uint32	openMode
	)

Creates a BFile and initializes it to the file referred to by the supplied BEntry and according to the specified open mode.

Parameters

entry	The BEntry referring to the file.
openMode	The mode in which the file should be opened.

See also: SetTo(const BEntry* entry, uint32 openMode)

Since: BeOS R3

◆ BFile() [5/6]

BFile::BFile	(	const char *	path,
		uint32	openMode
	)

Creates a BFile and initializes it to the file referred to by the supplied path name and according to the specified open mode.

Parameters

path	The file's path name.
openMode	The mode in which the file should be opened.

See also: SetTo(const char* path, uint32 openMode)

Since: BeOS R3

◆ BFile() [6/6]

BFile::BFile	(	const BDirectory *	dir,
		const char *	path,
		uint32	openMode
	)

Creates a BFile and initializes it to the file referred to by the supplied path name relative to the specified BDirectory and according to the specified open mode.

Parameters

dir	The BDirectory, relative to which the file's path name is given.
path	The file's path name relative to dir.
openMode	The mode in which the file should be opened.

See also: SetTo(const BDirectory* dir, const char* path, uint32 openMode)

Since: BeOS R3

◆ ~BFile()

BFile::~BFile ( )

virtual

Destroys the BFile object and frees all allocated resources.

If the file is properly initialized, the file descriptor is closed.

Since: BeOS R3

Member Function Documentation

◆ GetSize()

status_t BFile::GetSize ( off_t * size ) const

virtual

Gets the size of the file.

Parameters

size	The file size to fill out.

Returns: A status code.

See also: BStatable::GetSize()

Since: BeOS R3

Reimplemented from BPositionIO.

◆ IsReadable()

bool BFile::IsReadable ( ) const

Reports whether or not the file is readable.

Returns

true, if the BFile has been initialized properly and the file has been been opened for reading,
false, otherwise.

Since: BeOS R3

◆ IsWritable()

bool BFile::IsWritable ( ) const

Reports whether or not the file is writable.

Returns

true, if the BFile has been initialized properly and the file has been opened for writing,
false, otherwise.

Since: BeOS R3

◆ operator=()

BFile & BFile::operator= ( const BFile & file )

Assigns another BFile to this BFile.

If the other BFile is uninitialized, this one will be too. Otherwise it will refer to the same file using the same mode, unless an error occurs.

Parameters

file	The original BFile to assign from.

Returns: A reference to the assigned BFile.

Since: BeOS R3

◆ Position()

off_t BFile::Position ( ) const

virtual

Gets the current read/write position within the file.

Returns: The current read/write position relative to the beginning of the file or an error code.

Return values

B_ERROR	After a Seek() before the beginning of the file.
B_FILE_ERROR	The file has not been initialized.

Since: BeOS R3

Implements BPositionIO.

◆ Read()

ssize_t BFile::Read	(	void *	buffer,
		size_t	size
	)

virtual

Reads a number of bytes from the file into a buffer.

Parameters

buffer	The buffer the data from the file shall be written to.
size	The number of bytes that shall be read.

Returns: The number of bytes read or an error code.

Since: BeOS R3

Reimplemented from BPositionIO.

◆ ReadAt()

ssize_t BFile::ReadAt	(	off_t	location,
		void *	buffer,
		size_t	size
	)

virtual

Reads a number of bytes from a certain position within the file into a buffer.

Parameters

location	The position (in bytes) within the file from which the data shall be read.
buffer	The buffer the data from the file shall be written to.
size	The number of bytes that shall be read.

Returns: The number of bytes read or an error code.

Since: BeOS R3

Implements BPositionIO.

◆ Seek()

off_t BFile::Seek	(	off_t	offset,
		uint32	seekMode
	)

virtual

Seeks to another read/write position within the file.

It is allowed to seek past the end of the file. A subsequent call to Write() will pad the file with undefined data. Seeking before the beginning of the file will fail and the behavior of subsequent Read() or Write() invocations will be undefined.

Parameters

offset	New read/write position, depending on seekMode relative to the beginning or the end of the file or the current position.
seekMode	`SEEK_SET:` move relative to the beginning of the file. `SEEK_CUR:` move relative to the current position. `SEEK_END:` move relative to the end of the file.

Returns: The new read/write position relative to the beginning of the file or an error code.

Return values

B_ERROR	Trying to seek before the beginning of the file.
B_FILE_ERROR	The file is not properly initialized.

Since: BeOS R3

Implements BPositionIO.

◆ SetSize()

status_t BFile::SetSize ( off_t size )

virtual

Sets the size of the file.

If the file is shorter than size bytes it will be padded with unspecified data to the requested size. If it is larger, it will be truncated.

Note: There's no problem with setting the size of a BFile opened in B_READ_ONLY mode, unless the file resides on a read only volume.

Parameters

size	The new file size.

Returns: A status code.

Return values

B_OK	Everything went fine.
B_NOT_ALLOWED	Trying to set the size of a file on a read only volume.
B_DEVICE_FULL	There's not enough space left on the volume.

Since: BeOS R3

Reimplemented from BPositionIO.

◆ SetTo() [1/4]

status_t BFile::SetTo	(	const BDirectory *	dir,
		const char *	path,
		uint32	openMode
	)

Re-initializes the BFile to the file referred to by the supplied path name relative to the specified BDirectory and according to the specified open mode.

Parameters

dir	The BDirectory, relative to which the file's path name is given.
path	The file's path name relative to dir.
openMode	The mode in which the file should be opened.

Returns: A status code.

Return values

B_OK	Everything went fine.
B_BAD_VALUE	`NULL` dir or path or bad openMode.
B_ENTRY_NOT_FOUND	File not found or failed to create file.
B_FILE_EXISTS	File exists and `B_FAIL_IF_EXISTS` was passed.
B_PERMISSION_DENIED	File permissions didn't allow operation.
B_NO_MEMORY	Insufficient memory for operation.
B_LINK_LIMIT	Indicates a cyclic loop within the file system.
B_BUSY	A node was busy.
B_FILE_ERROR	A general file error.
B_NO_MORE_FDS	The application has run out of file descriptors.

Since: BeOS R3

◆ SetTo() [2/4]

status_t BFile::SetTo	(	const BEntry *	entry,
		uint32	openMode
	)

Re-initializes the BFile to the file referred to by the supplied BEntry and according to the specified open mode.

Parameters

entry	the BEntry referring to the file
openMode	the mode in which the file should be opened

Returns: A status code.

Return values

B_OK	Everything went fine.
B_BAD_VALUE	`NULL` entry or bad openMode.
B_ENTRY_NOT_FOUND	File not found or failed to create file.
B_FILE_EXISTS	File exists and `B_FAIL_IF_EXISTS` was passed.
B_PERMISSION_DENIED	File permissions didn't allow operation.
B_NO_MEMORY	Insufficient memory for operation.
B_LINK_LIMIT	Indicates a cyclic loop within the file system.
B_BUSY	A node was busy.
B_FILE_ERROR	A general file error.
B_NO_MORE_FDS	The application has run out of file descriptors.

Since: BeOS R3

◆ SetTo() [3/4]

status_t BFile::SetTo	(	const char *	path,
		uint32	openMode
	)

Re-initializes the BFile to the file referred to by the supplied path name and according to the specified open mode.

Parameters

path	The file's path name.
openMode	The mode in which the file should be opened.

Returns: A status code.

Return values

B_OK	Everything went fine.
B_BAD_VALUE	`NULL` path or bad openMode.
B_ENTRY_NOT_FOUND	File not found or failed to create file.
B_FILE_EXISTS	File exists and `B_FAIL_IF_EXISTS` was passed.
B_PERMISSION_DENIED	File permissions didn't allow operation.
B_NO_MEMORY	Insufficient memory for operation.
B_LINK_LIMIT	Indicates a cyclic loop within the file system.
B_BUSY	A node was busy.
B_FILE_ERROR	A general file error.
B_NO_MORE_FDS	The application has run out of file descriptors.

Since: BeOS R3

◆ SetTo() [4/4]

status_t BFile::SetTo	(	const entry_ref *	ref,
		uint32	openMode
	)

Re-initializes the BFile to the file referred to by the supplied entry_ref and according to the specified open mode.

Parameters

ref The entry_ref referring to the file.

openMode

The mode in which the file should be opened openMode must be a bitwise or of exactly one of the flags.

B_READ_ONLY: The file is opened read only.
B_WRITE_ONLY: The file is opened write only.
B_READ_WRITE: The file is opened for random read/write access. and any number of the flags
B_CREATE_FILE: A new file will be created, if it does not already exist.
B_FAIL_IF_EXISTS: If the file does already exist and B_CREATE_FILE is set, SetTo() fails.
B_ERASE_FILE: An already existing file is truncated to zero size.
B_OPEN_AT_END: Seek() to the end of the file after opening.

Returns: A status code.

Return values

B_OK	Everything went fine.
B_BAD_VALUE	`NULL` ref or bad openMode.
B_ENTRY_NOT_FOUND	File not found or failed to create file.
B_FILE_EXISTS	File exists and `B_FAIL_IF_EXISTS` was passed.
B_PERMISSION_DENIED	File permissions didn't allow operation.
B_NO_MEMORY	Insufficient memory for operation.
B_LINK_LIMIT	Indicates a cyclic loop within the file system.
B_BUSY	A node was busy.
B_FILE_ERROR	A general file error.
B_NO_MORE_FDS	The application has run out of file descriptors.

Since: BeOS R3

◆ Write()

ssize_t BFile::Write	(	const void *	buffer,
		size_t	size
	)

virtual

Writes a number of bytes from a buffer into the file.

Parameters

buffer	The buffer containing the data to be written to the file.
size	The number of bytes that shall be written.

Returns: The number of bytes actually written or an error code.

Since: BeOS R3

Reimplemented from BPositionIO.

◆ WriteAt()

ssize_t BFile::WriteAt	(	off_t	location,
		const void *	buffer,
		size_t	size
	)

virtual

Writes a number of bytes from a buffer at a certain position into the file.

Parameters

location	The position (in bytes) within the file at which the data shall be written.
buffer	The buffer containing the data to be written to the file.
size	The number of bytes that shall be written.

Returns: The number of bytes actually written or an error code.

Since: BeOS R3

Implements BPositionIO.

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ BFile() [1/6]

◆ BFile() [2/6]

◆ BFile() [3/6]

◆ BFile() [4/6]

◆ BFile() [5/6]

◆ BFile() [6/6]

◆ ~BFile()

Member Function Documentation

◆ GetSize()

◆ IsReadable()

◆ IsWritable()

◆ operator=()

◆ Position()

◆ Read()

◆ ReadAt()

◆ Seek()

◆ SetSize()

◆ SetTo() [1/4]

◆ SetTo() [2/4]

◆ SetTo() [3/4]

◆ SetTo() [4/4]

◆ Write()

◆ WriteAt()