casacore::RegularFileIO Class Reference

Class for IO on a regular file. More...

#include <RegularFileIO.h>

Inheritance diagram for casacore::RegularFileIO:

Public Member Functions
	RegularFileIO (const RegularFile &regularFile, ByteIO::OpenOption=ByteIO::Old, uInt filebufSize=0)
	Create an IO stream object for a regular file with the given name. More...
	~RegularFileIO ()
virtual void	reopenRW ()
	Reopen the underlying file for read/write access. More...
virtual String	fileName () const
	Get the file name of the file attached. More...
Public Member Functions inherited from casacore::FilebufIO
	FilebufIO ()
	Default constructor. More...
	FilebufIO (int fd, uInt bufferSize=16384)
	Construct from the given file descriptor. More...
void	attach (int fd, uInt bufferSize=16384)
	Attach to the given file descriptor. More...
virtual	~FilebufIO ()
	The destructor closes the file when it was owned and opened and not closed yet. More...
virtual void	write (Int64 size, const void *buf)
	Write the number of bytes. More...
virtual Int64	read (Int64 size, void *buf, Bool throwException=True)
	Read size bytes from the File. More...
virtual void	flush ()
	Flush the current buffer. More...
virtual void	resync ()
	Resync the file (i.e. More...
virtual Int64	length ()
	Get the length of the byte stream. More...
virtual Bool	isReadable () const
	Is the IO stream readable? More...
virtual Bool	isWritable () const
	Is the IO stream writable? More...
virtual Bool	isSeekable () const
	Is the IO stream seekable? More...
uInt	bufferSize () const
	Get the buffer size. More...
Public Member Functions inherited from casacore::ByteIO
	ByteIO ()
	The constructor does nothing. More...
virtual	~ByteIO ()
virtual void	pwrite (Int64 size, Int64 offset, const void *buf)
	Write size bytes to the byte stream at offset. More...
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. More...
Int64	seek (Int offset, ByteIO::SeekOption=ByteIO::Begin)
	This function sets the position on the given offset. More...
Int64	seek (Int64 offset, ByteIO::SeekOption=ByteIO::Begin)
virtual void	fsync ()
	Fsync the file (i.e. More...

Static Public Member Functions
static int	openCreate (const RegularFile &file, ByteIO::OpenOption, Bool useODirect=False)
	Convenience function to open or create a file. More...

Private Member Functions
	RegularFileIO (const RegularFileIO &that)
	Copy constructor, should not be used. More...
RegularFileIO &	operator= (const RegularFileIO &that)
	Assignment, should not be used. More...

Private Attributes
OpenOption	itsOption
RegularFile	itsRegularFile

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::FilebufIO
void	detach (Bool closeFile=False)
	Detach the FILE. More...
void	fillRWFlags (int fd)
	Determine if the file descriptor is readable and/or writable. More...
void	fillSeekable ()
	Determine if the file is seekable. More...
virtual Int64	doSeek (Int64 offset, ByteIO::SeekOption)
	Reset the position pointer to the given value. More...
void	setBuffer (Int64 bufSize)
	Set a new buffer size. More...
void	writeBuffer (Int64 offset, const char *buf, Int64 size)
	Write a buffer of given length into the file at given offset. More...
Int64	readBuffer (Int64 offset, char *buf, Int64 size, Bool throwException)
	Read a buffer of given length from the file at given offset. More...
void	writeBlock (Int64 size, const char *buf)
	Write a block into the stream at the current offset. More...
Int64	readBlock (Int64 size, char *buf, Bool throwException)
	Read a block from the stream at the current offset. 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). More...
ByteIO &	operator= (const ByteIO &byteIO)

Detailed Description

Class for IO on a regular file.

Intended use:

Public interface

Review Status

Reviewed By:

Friso Olnon

Date Reviewed:

1996/11/06

Test programs:

tByteIO

Prerequisite

• FilebufIO class

Synopsis

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

The class is derived from FilebufIO, which contains all functions to access the file. The description of this class explains the use of the filebufSize argument in the constructor.

Example

// Create a file (which should not exist yet).
RegularFileIO regio (RegularFile("file.name"), ByteIO::NewNoReplace);
// Use that as the sink of AipsIO.
AipsIO stream (&regio);
// 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 81 of file RegularFileIO.h.

Constructor & Destructor Documentation

casacore::RegularFileIO::RegularFileIO ( const RegularFile &  regularFile, ByteIO::OpenOption  = ByteIO::Old, uInt  filebufSize = 0  )

explicit

Create an IO stream object for a regular file with the given name.

The ByteIO option determines if the file will be created or opened for input and/or output.
The argument filebufSize defines the length of the internal buffer in the underlying FilebufIO object. A zero length uses an appropriate default.

casacore::RegularFileIO::~RegularFileIO

(

)

casacore::RegularFileIO::RegularFileIO ( const RegularFileIO &  that )

private

Copy constructor, should not be used.

Member Function Documentation

virtual String casacore::RegularFileIO::fileName ( ) const

virtual

Get the file name of the file attached.

Reimplemented from casacore::FilebufIO.

static int casacore::RegularFileIO::openCreate ( const RegularFile &  file, ByteIO::OpenOption  , Bool  useODirect = False  )

static

Convenience function to open or create a file.

Optionally it is checked if the file does not exist yet. If useODirect=True and if supported by the OS, the file will be opened with O_DIRECT which bypasses the kernel's file cache for more predictable I/O behaviour. It requires the size and the alignment of the data to be read/written to be a multiple of the the disk's logival block size. It returns the file descriptor.

RegularFileIO& casacore::RegularFileIO::operator= ( const RegularFileIO &  that )

private

Assignment, should not be used.

virtual void casacore::RegularFileIO::reopenRW ( )

virtual

Reopen the underlying file for read/write access.

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

Reimplemented from casacore::ByteIO.

Member Data Documentation

OpenOption casacore::RegularFileIO::itsOption

private

Definition at line 117 of file RegularFileIO.h.

RegularFile casacore::RegularFileIO::itsRegularFile

private

Definition at line 118 of file RegularFileIO.h.

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

• casa/casacore/casa/IO/RegularFileIO.h