IFileDesc Class Reference

Abstract interface of fd (file descriptor). More...

#include <file.hh>

Inheritance diagram for IFileDesc:

Public Member Functions
	IFileDesc ()
	Construct a default object.
virtual	~IFileDesc ()
	Destroy this object. More...
bool	valid () const
	Test if this object is a valid file descriptor. More...
int	fd () const
	Get fd (file descriptor). More...
virtual int	fdType () const =0
	Get type id of this object. More...
virtual const char *	fdTypeName () const =0
	Get type name of this object. More...
std::string	filename () const
	Get file name opened by this object. More...
off_t	length () const
	Get byte size of file opened by this object. More...
bool	deleted () const
	Test if file is deleted. More...
bool	block (bool on)
	Set block/non-block for operations. More...
void	close ()
	Close this fd.
virtual std::string	toString () const
	Get readable description of this object. More...

Static Public Member Functions
static std::string	ErrMsg ()
	Get latest errno and error message. More...

Static Public Attributes
static const int	kInvalidFd = -1

Detailed Description

Abstract interface of fd (file descriptor).

Constructor & Destructor Documentation

virtual IFileDesc::~IFileDesc ( )

inlinevirtual

Destroy this object.

Release any resources if necessary.

Member Function Documentation

bool IFileDesc::block ( bool  on )

inline

Set block/non-block for operations.

Parameters

on	true: all IO operations will be BLOCK by default false: all IO operations will be NONBLOCK by default

Returns

true if succeeded; false otherwise

See also

ErrMsg

bool IFileDesc::deleted ( ) const

inline

Test if file is deleted.

A file could be removed even if you're reading or writing it. So it's necessary to test this status, or you may lost all changes to the file.

Returns

true if file is deleted; false otherwise

static std::string IFileDesc::ErrMsg ( )

inlinestatic

Get latest errno and error message.

Returns

Description of latest error

int IFileDesc::fd ( ) const

inline

Get fd (file descriptor).

Returns

fd

virtual int IFileDesc::fdType ( ) const

pure virtual

Get type id of this object.

Any concrete class derived from IFileDesc shall define a distinct type id named kFdType, so it's possible to check this id and determine what the object really is.
Currently following kFdTypes are defined:

Type Id	Value
CFile::kFdType	1
CTcpConnSocket::kFdType	2
CListenSocket::kFdType	3
CUdpSocket::kFdType	4
CPosixShmFile::kFdType	5
CEpoll::kFdType	6

Returns

Type id of this object

See also

kFdType

Implemented in CListenSocket, CTcpConnSocket, CUdpSocket, CFile, CEpoll, and CPosixShmFile.

virtual const char* IFileDesc::fdTypeName ( ) const

pure virtual

Get type name of this object.

Any concrete class derived from IFileDesc must give a readable name to identify itself.

Returns

Readable type name

Implemented in CListenSocket, CTcpConnSocket, CUdpSocket, CFile, CEpoll, and CPosixShmFile.

std::string IFileDesc::filename ( ) const

inline

Get file name opened by this object.

Returns

A file name, or an empty string if any error occurs

See also

ErrMsg

off_t IFileDesc::length ( ) const

inline

Get byte size of file opened by this object.

Returns

• -1: Failed
• others: Byte size of file

See also

ErrMsg

virtual std::string IFileDesc::toString ( ) const

inlinevirtual

Get readable description of this object.

Returns

Description string

Reimplemented in CFile, ISocket, CEpoll, and CPosixShmFile.

bool IFileDesc::valid ( ) const

inline

Test if this object is a valid file descriptor.

Returns

true if it's valid; false otherwise

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

• file.hh