#include <MFFileIO.h>

Public Member Functions
	MFFileIO (const std::shared_ptr< MultiFileBase > &, const String &name, ByteIO::OpenOption=ByteIO::Old)
	Open or create a virtual file with the given name.

	~MFFileIO () override
	The destructor flushes and closes the file.

Int64	read (Int64 size, void *buf, Bool throwException=True) override
	Read `size` bytes from the byte stream.

void	write (Int64 size, const void *buffer) override
	Write a block at the current offset.

void	reopenRW () override
	Reopen the file (and possibly underlying MultiFileBase) for read/write access.

void	remove ()
	Remove the file from the MultiFileBase object.

void	flush () override
	Flush the file by writing all dirty data and all header info.

Int64	length () override
	Get the length of the file.

Bool	isReadable () const override
	The file is always readable.

Bool	isWritable () const override
	Is the file writable?

Bool	isSeekable () const override
	The file is always seekable.

String	fileName () const override
	Get the file name of the file attached.

void	fsync () override
	Fsync the file (i.e.

void	truncate (Int64 size) override
	Truncate the file to the given size.

Int64	doSeek (Int64 offset, ByteIO::SeekOption) override
	Reset the position pointer to the given value.

const MultiFileInfo &	getInfo () const
	Get the MultiFileInfo object for this file.

Public Member Functions inherited from casacore::ByteIO
	ByteIO ()
	The constructor does nothing.

virtual	~ByteIO ()

virtual void	pwrite (Int64 size, Int64 offset, const void *buf)
	Write `size` bytes to the byte stream at `offset`.

virtual Int64	pread (Int64 size, Int64 offset, void *buf, Bool throwException=True)
	Like read but reads from offset of start of the file The file offset is not changed.

Int64	seek (Int offset, ByteIO::SeekOption=ByteIO::Begin)
	This function sets the position on the given offset.

Int64	seek (Int64 offset, ByteIO::SeekOption=ByteIO::Begin)

virtual void	resync ()
	Resync the file (i.e.

Private Attributes
std::shared_ptr< MultiFileBase >	itsFile

Int64	itsPosition

String	itsName

Int	itsId

Bool	itsIsWritable

Additional Inherited Members
Public Types inherited from casacore::ByteIO
enum	OpenOption { Old , Update , Append , New , NewNoReplace , Scratch , Delete }
	Define the possible ByteIO open options. More...

enum	SeekOption { Begin , Current , End }
	Define the possible seek options. More...

Protected Member Functions inherited from casacore::ByteIO
	ByteIO (const ByteIO &byteIO)
	Make copy constructor and assignment protected, so a user cannot use them (but a derived class can).

ByteIO &	operator= (const ByteIO &byteIO)

Detailed Description

Class for IO on a virtual file in a MultiFileBase

Intended use:

Public interface

Review Status

Reviewed By:: Friso Olnon
Date Reviewed:: 1996/11/06
Test programs:: tByteIO

Synopsis

This class is a specialization of class ByteIO. It uses a MultiFileBase as the data store.

Similar to a regular file it is possible to read and write data and to seek in the file. The object keeps track of the current file offset.

Example

// Create a new MultiFile using a block size of 1 MB.
shared_ptr<MultiFileBase> mfile
(new MultiFile("file.mf', ByteIO::New, 1048576));
// Create a virtual file in it.
MFFileIO mf1(mfile, "mf1", ByteIO::New);
// Use it (for example) as the sink of AipsIO.
AipsIO stream (&mf1);
// Write values.
stream << (Int)10;
stream << True;
// Seek to beginning of file and read data in.
stream.setpos (0);
Int vali;
Bool valb;
stream >> vali >> valb;

Definition at line 76 of file MFFileIO.h.

Constructor & Destructor Documentation

◆ MFFileIO()

casacore::MFFileIO::MFFileIO	(	const std::shared_ptr< MultiFileBase > &	,
		const String &	name,
		ByteIO::OpenOption	= `ByteIO::Old`
	)

Open or create a virtual file with the given name.

Note that only the basename of the file name is actually used. It is created in the given MultiFileBase.

◆ ~MFFileIO()

casacore::MFFileIO::~MFFileIO ( )

override

The destructor flushes and closes the file.

Member Function Documentation

◆ doSeek()

Int64 casacore::MFFileIO::doSeek	(	Int64	offset,
		ByteIO::SeekOption
	)

overridevirtual

Reset the position pointer to the given value.

It returns the new position.

Implements casacore::ByteIO.

◆ fileName()

String casacore::MFFileIO::fileName ( ) const

overridevirtual

Get the file name of the file attached.

Reimplemented from casacore::ByteIO.

◆ flush()

void casacore::MFFileIO::flush ( )

overridevirtual

Flush the file by writing all dirty data and all header info.

Reimplemented from casacore::ByteIO.

◆ fsync()

void casacore::MFFileIO::fsync ( )

overridevirtual

Fsync the file (i.e.

force the data to be physically written).

Int64 casacore::MFFileIO::read	(	Int64	size,
		void *	buf,
		Bool	throwException = `True`
	)

overridevirtual

Read size bytes from the byte stream.

Returns the number of bytes actually read, or a negative number if an error occurred. Will also throw an Exception (AipsError) if the requested number of bytes could not be read unless throwException is set to False.

Implements casacore::ByteIO.

◆ remove()

void casacore::MFFileIO::remove ( )

Remove the file from the MultiFileBase object.

It makes the object invalid by setting the fileId to -1.

◆ reopenRW()

void casacore::MFFileIO::reopenRW ( )

overridevirtual

Reopen the file (and possibly underlying MultiFileBase) for read/write access.

Nothing will be done if the stream is writable already. An exception will be thrown if it is not possible to reopen it for read/write access.

Reimplemented from casacore::ByteIO.

◆ truncate()

void casacore::MFFileIO::truncate ( Int64 size )

overridevirtual

Truncate the file to the given size.

Reimplemented from casacore::ByteIO.

◆ write()

void casacore::MFFileIO::write	(	Int64	size,
		const void *	buffer
	)

overridevirtual

Write a block at the current offset.

Implements casacore::ByteIO.

Member Data Documentation

◆ itsFile

std::shared_ptr<MultiFileBase> casacore::MFFileIO::itsFile

private

Definition at line 140 of file MFFileIO.h.

◆ itsId

Int casacore::MFFileIO::itsId

private

Definition at line 143 of file MFFileIO.h.

◆ itsIsWritable

Bool casacore::MFFileIO::itsIsWritable

private

Definition at line 144 of file MFFileIO.h.

◆ itsName

String casacore::MFFileIO::itsName

private

Definition at line 142 of file MFFileIO.h.

◆ itsPosition

Int64 casacore::MFFileIO::itsPosition

private

Definition at line 141 of file MFFileIO.h.

The documentation for this class was generated from the following file:

casa/IO/MFFileIO.h

Public Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Intended use:

Review Status

Synopsis

Example

Constructor & Destructor Documentation

◆ MFFileIO()

◆ ~MFFileIO()

Member Function Documentation

◆ doSeek()

◆ fileName()

◆ flush()

◆ fsync()

◆ getInfo()

◆ isReadable()

◆ isSeekable()

◆ isWritable()

◆ length()

◆ read()

◆ remove()

◆ reopenRW()

◆ truncate()

◆ write()

Member Data Documentation

◆ itsFile

◆ itsId

◆ itsIsWritable

◆ itsName

◆ itsPosition