atoms::Seekable Class Reference
[IO Subsystem]

#include <stream.hh>

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Detailed Description

Mix-in to make a Stream or BufferedStream seekable.

Definition at line 105 of file stream.hh.

Public Types
enum	Origin { oSet, oCur, oEnd }
	The origin for a seek operation. More...
Public Member Functions
virtual off_t	seek (off_t offset, Origin origin=oSet)=0
	Seek to the given position in the stream.
virtual bool	isAppending () const=0
	Returns true iff the stream is in "append mode".
off_t	tell ()
	Returns the current position in the stream.
Protected Attributes
boost::weak_ptr< IOHandle >	thisWeak
	A weak pointer to 'this' for source in IOError.

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Member Enumeration Documentation

enum atoms::Seekable::Origin

The origin for a seek operation. Enumeration values: oSet  Set from the beginning of the stream. oCur  Set relative to the current position. oEnd  Set relative to the end of the stream. Definition at line 108 of file stream.hh.

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Member Function Documentation

virtual bool atoms::Seekable::isAppending (   )  const [pure virtual]

Returns true iff the stream is in "append mode". In this mode, the stream is atomically positioned at the end of file at the beginning of every write operation. Precondition: The stream is open. Implemented in atoms::SeekableUNIXStream.

virtual off_t atoms::Seekable::seek (  off_t  offset, Origin  origin = oSet )  [pure virtual]

Seek to the given position in the stream. Precondition: This is a seekable stream. Parameters: offset  The offset, in bytes, from the given origin. May be negative for oCur or oEnd origins. origin  The origin; see enumeration definition. Exceptions: IOError  as appropriate. See documentation for the specific subclass. Returns: The resulting offset from the beginning of the file. Implemented in atoms::SeekableUNIXStream. Referenced by tell().

off_t atoms::Seekable::tell (   )  [inline]

Returns the current position in the stream. Definition at line 135 of file stream.hh. References oCur, and seek().

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Member Data Documentation

boost::weak_ptr<IOHandle> atoms::IOHandle::thisWeak [protected, inherited]

A weak pointer to 'this' for source in IOError. Definition at line 175 of file gen.hh.

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

• atoms/stream.hh

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