oestream¶
class oestream
This class represents oestream.
The oestream class is the base class which sets up the platform independent interface for streaming any type of data.
- The following classes derive from this class:
Constructors¶
oestream()
Creates an instance of an oestream. This class exists solely to provide an interface, therefore, instances of this class have no independently meaningful functionality.
operator bool¶
operator bool() const
Evaluates the stream to a Boolean value based on whether the end of
the stream has been reached. This is equivalent to !eof()
.
length¶
oefpos_t length()
Returns the number of bytes that have been read from or written
to the stream in the last
read
or
write
call.
seek¶
bool seek(oefpos_t pos)
bool seek(oefpos_t offset, seek_dir dir)
Sets the current position of the data pointer. This is accomplished by specifying the desired position or by specifying an offset distance and a directionality from the current position. Directionality is specified using the following enumeration:
enum seek_dir { beg = 0, cur = 1, end = 2 };
size¶
oefpos_t size()
If possible, returns the size of the stream in bytes. For
oeostreams
this is always
zero
.
Note
For oeistreams
this may not
be possible to calculate without reading, e.g., when the
stream is a socket or pipe. In this case the implementation
may return 0
.