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Symbian OS v6.1 Edition for C++ »
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RReadStream
Location:
s32strm.h
Link against: estor.lib
RReadStream
Support
Supported from 5.0
Description
The read stream interface. The process of internalising from a
stream is achieved through a reference to an object of this type.
A store aware class defines an implements an
InternalizeL() member function which is used to internalise that
object and takes a reference to an RReadStream as the interface to
the read stream.
Defined in RReadStream:
Attach(), Close(), Detach(), Pop(), PushL(), RReadStream(), ReadInt16L(), ReadInt32L(), ReadInt8L(), ReadL(), ReadReal32L(), ReadReal64L(), ReadUint16L(), ReadUint32L(), ReadUint8L(), Release(), Source()
Construction and destruction
RReadStream();
Description
Sets the stream buffer source to NULL, which implies that it is
safe to close
See also:
RReadStream(MStreamBuf* aSource);
Description
Constructs a read stream over the supplied stream
buffer.
Parameters
MStreamBuf* aSource |
The stream buffer used to read from the read stream. |
|
See also:
void ReadL(TDes8& aDes);
Description
Reads sufficient data from this stream to fill the specified 8 bit
descriptor up to its maximum length. No other information is read from this
read stream.
Parameters
TDes8& aDes |
A reference to a modifiable descriptor which is to receive the data
read from this stream. Passing the build independent type
TDes& allows the compiler to choose the appropriate
ReadL() variant (i.e the 8 bit or the 16 bit) at build
time. |
|
Leave codes
|
If the length of data available in the stream is less than the
maximum length of aDes , then the function leaves with
KErrEof . |
|
void ReadL(TDes16& aDes);
Description
Reads sufficient data from this stream to fill the specified 16 bit
descriptor up to its maximum length. No other information is read from this
read stream.
Parameters
TDes16& aDes |
A reference to a modifiable type descriptor which is to receive the
data read from this stream. Passing the build independent type
TDes& allows the compiler to choose the appropriate
ReadL() variant (i.e the 8 bit or the 16 bit) at build
time. |
|
Leave codes
|
If the length of data available in the stream is less than the
maximum length of aDes , then the function leaves with
KErrEof . |
|
void ReadL(TDes8& aDes,TInt aLength);
Description
Reads data of specified length from this stream into the specified 8
bit descriptor. No other information is read from this
stream.
Parameters
TDes8& aDes |
A reference to a modifiable type descriptor which is to receive the
data read from this stream. Passing the build independent type
TDes& allows the compiler to choose the appropriate
ReadL() variant (i.e the 8 bit or the 16 bit) at build
time. |
TInt aLength |
The length of data to be read from this stream. This value must be
non-negative and must not be greater than the maximum length of the descriptor
otherwise the function raises a USER 23 panic. |
|
Leave codes
|
If the length of data available in the stream is less than
aLength , then the function leaves with KErrEof .
|
|
void ReadL(TDes16& aDes,TInt aLength);
Description
Reads data of specified length from this stream into the specified 16 bit
descriptor. No other information is read from this stream.
Parameters
TDes16& aDes |
A reference to a modifiable type descriptor which is to receive the data
read from this stream. Passing the build independent type
TDes& allows the compiler to choose the appropriate
ReadL() variant (i.e the 8 bit or the 16 bit) at build
time. |
TInt aLength |
The length of data to be read from this stream. This value must be
non-negative and must not be greater than the maximum length of the descriptor
otherwise the function raises a USER 11 panic. |
|
Leave codes
|
If the length of data available in the stream is less than
aLength , then the function leaves with KErrEof .
|
|
void ReadL(TDes8& aDes,TChar aDelim);
Description
Reads data from this stream into the 8 bit descriptor, until either the
specified delimiter is encountered or the descriptor is filled to its maximum
length.
The resulting data in aDes always includes the delimiter
aDelim, if aDes is large enough.
Parameters
TDes8& aDes |
A reference to a modifiable type descriptor which is to receive the data
read from this stream. Passing the build independent type
TDes& allows the compiler to choose the appropriate
ReadL() variant (i.e the 8 bit or the 16 bit) at build
time. |
TChar aDelim |
The delimiter marking the end of the data in the stream. |
|
Leave codes
|
The function leaves with KErrEof , if the stream is
exhausted before a delimiter is found. |
|
void ReadL(TDes16& aDes,TChar aDelim);
Description
Reads data from this stream into the 16 bit descriptor, until either the
specified delimiter is encountered or the descriptor is filled to its maximum
length.
The resulting data in aDes always includes the delimiter
aDelim, if aDes is large enough.
Parameters
TDes16& aDes |
A reference to a modifiable type descriptor which is to receive the data
read from this stream. Passing the build independent type
TDes& allows the compiler to choose the appropriate
ReadL() variant (i.e the 8 bit or the 16 bit) at build
time. |
TChar aDelim |
The delimiter marking the end of the data in the stream. |
|
Leave codes
|
The function leaves with KErrEof , if the stream is
exhausted before a delimiter is found. |
|
void ReadL(TUint8* aPtr,TInt aLength);
Description
Reads data of specified length from this stream into the location defined
by the specified TUint8 pointer.
Parameters
TUint8* aPtr |
The target location for the streamed in data. |
TInt aLength |
The length of data to be streamed in. |
|
Leave codes
|
If the length of data available in the stream is less than the length of
data requested, then the function leaves with KErrEof . |
|
void ReadL(TUint16* aPtr,TInt aLength);
Description
Reads data of specified length from this stream into the location defined
by the specified TUint16 pointer.
Parameters
TUint16* aPtr |
The target location for the streamed in data. |
TInt aLength |
The length of data to be streamed in. |
|
Leave codes
|
If the length of data available in the stream is less than the length of
data requested, then the function leaves with KErrEof . |
|
void ReadL(RWriteStream& aStream);
Description
Writes the content of this stream to the specified write
stream.
Parameters
RWriteStream& aStream |
A reference to the write stream to which this stream is to be
written. |
|
void ReadL(RWriteStream& aStream,TInt aLength);
Description
Writes a specified length of the content of this stream to the specified
write stream.
Parameters
RWriteStream& aStream |
A reference to the write stream to which this stream is to be
written. |
TInt aLength |
The length of data from this stream to be written to
aStream. |
|
void ReadL(TInt aLength);
Description
Discards data of specified length read from this
stream.
Parameters
TInt aLength |
The length of data to be discarded from this read stream. |
|
Leave codes
|
If the length of data available in the stream is less than the length of
data requested, then the function leaves with KErrEof . |
|
TInt8 ReadInt8L();
Description
Internalises a TInt8 value The function reads an
8 bit value from this stream and interprets it as a
TInt8.
Return value
TInt8 |
The 8 bit value read from this stream. |
|
Leave codes
|
If the length of data available in the stream is less than the length of
data requested, then the function leaves with KErrEof . |
|
TInt16 ReadInt16L();
Description
Internalises a TInt16 value. The function reads a
16 bit value from this stream and interprets it as a
TInt16.
Return value
TInt16 |
The 16 bit value read from this stream. |
|
Leave codes
|
If the length of data available in the stream is less than the length of
data requested, then the function leaves with KErrEof . |
|
TInt32 ReadInt32L();
Description
Internalises a TInt32 value. The function reads a
32 bit value from this stream and interprets it as a
TInt32.
Return value
TInt32 |
The 32 bit value read from this stream. |
|
Leave codes
|
If the length of data available in the stream is less than the length of
data requested, then the function leaves with KErrEof . |
|
TUint8 ReadUint8L();
Description
Internalises a TUint8 value. The function reads an
8 bit value from this stream and interprets it as a
TUint8.
Return value
TUint8 |
The 8 bit value read from this stream. |
|
Leave codes
|
If the length of data available in the stream is less than the length of
data requested, then the function leaves with KErrEof . |
|
TUint16 ReadUint16L();
Description
Internalises a TUint16 value. The function reads a
16 bit value from this stream and interprets it as a
TUint16.
Return value
TUint16 |
The 16 bit value read from this stream. |
|
Leave codes
|
If the length of data available in the stream is less than the length of
data requested, then the function leaves with KErrEof . |
|
TUint32 ReadUint32L();
Description
Internalises a TUint32 value. The function reads a
32 bit value from this stream and interprets it as a
TUint32.
Return value
TUint32 |
The 32 bit value read from this stream. |
|
Leave codes
|
If the length of data available in the stream is less than the length of
data requested, then the function leaves with KErrEof . |
|
TReal32 ReadReal32L();
Description
Internalises a TReal32 value. The function reads a
32 bit value from this stream and interprets it as a
TReal32.
Return value
TReal32 |
The 32 bit value read from this read stream. |
|
Leave codes
|
If the length of data available in the stream is less than the length of
data requested, then the function leaves with KErrEof . |
|
TReal64 ReadReal64L();
Description
Internalises a TReal64 value. The function reads a
64 bit value from this stream and interprets it as a
TReal64.
Return value
TReal64 |
The 64 bit value read from this stream. |
|
Leave codes
|
If the length of data available in the stream is less than the length of
data requested, then the function leaves with KErrEof . |
|
void PushL();
Description
Puts a cleanup item for this read stream object onto the cleanup stack.
This allows allocated resources to be cleaned up if a subsequent leave
occurs.
void Pop();
Description
Removes the cleanup item for this read stream object from the cleanup
stack.
void Release();
Description
Frees resources before abandoning the stream.
Note that, if a cleanup item for the stream was placed on the cleanup
stack when the stream was opened by a call to OpenLC(), then this
function need not be called explicitly; clean up is implicitly done by
CleanupStack::PopAndDestroy().
void Close();
Description
Frees resources used by the stream.
See also:
Attaching & Detaching stream buffers
protected: void Attach(MStreamBuf* aSource);
Description
Sets the stream buffer source for this read stream. The existing source
(if there is one) will be discarded.
This is useful for derived classes, enabling them to set the source
following construction.
Note:
Parameters
MStreamBuf* aSource |
The new source stream buffer for this read stream. |
|
See also:
protected: void Detach();
Description
Sets the stream buffer source for this read stream to NULL. The existing
source, if there is one, will be discarded.
Note that Release() is not called on any discarded stream
buffer.
See also:
MStreamBuf* Source();
Description
Gets the underlying stream buffer for the read stream. This provides
access to the stream-buffer implementation used by the read stream.
Note:
Return value
MStreamBuf* |
The underlying stream buffer for the read stream. |
|
See also:
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