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<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>QDataStream Class Reference</h1>
<p>The QDataStream class provides serialization of
binary data to a QIODevice.
<a href="#details">More...</a>
<p><tt>#include <<a href="qdatastream-h.html">qdatastream.h</a>></tt>
<p><a href="qdatastream-members.html">List of all member functions.</a>
<h2>Public Members</h2>
<ul>
<li><div class=fn><a href="#QDataStream"><b>QDataStream</b></a> ()</div></li>
<li><div class=fn><a href="#QDataStream-2"><b>QDataStream</b></a> ( QIODevice * d )</div></li>
<li><div class=fn><a href="#QDataStream-3"><b>QDataStream</b></a> ( QByteArray a, int mode )</div></li>
<li><div class=fn>virtual <a href="#~QDataStream"><b>~QDataStream</b></a> ()</div></li>
<li><div class=fn>QIODevice * <a href="#device"><b>device</b></a> () const</div></li>
<li><div class=fn>void <a href="#setDevice"><b>setDevice</b></a> ( QIODevice * d )</div></li>
<li><div class=fn>void <a href="#unsetDevice"><b>unsetDevice</b></a> ()</div></li>
<li><div class=fn>bool <a href="#atEnd"><b>atEnd</b></a> () const</div></li>
<li><div class=fn>bool eof () const <em>(obsolete)</em></div></li>
<li><div class=fn>enum <a href="#ByteOrder-enum"><b>ByteOrder</b></a> { BigEndian, LittleEndian }</div></li>
<li><div class=fn>int <a href="#byteOrder"><b>byteOrder</b></a> () const</div></li>
<li><div class=fn>void <a href="#setByteOrder"><b>setByteOrder</b></a> ( int bo )</div></li>
<li><div class=fn>bool <a href="#isPrintableData"><b>isPrintableData</b></a> () const</div></li>
<li><div class=fn>void <a href="#setPrintableData"><b>setPrintableData</b></a> ( bool enable )</div></li>
<li><div class=fn>int <a href="#version"><b>version</b></a> () const</div></li>
<li><div class=fn>void <a href="#setVersion"><b>setVersion</b></a> ( int v )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-gt-gt"><b>operator>></b></a> ( Q_INT8 & i )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-gt-gt-2"><b>operator>></b></a> ( Q_UINT8 & i )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-gt-gt-3"><b>operator>></b></a> ( Q_INT16 & i )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-gt-gt-4"><b>operator>></b></a> ( Q_UINT16 & i )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-gt-gt-5"><b>operator>></b></a> ( Q_INT32 & i )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-gt-gt-6"><b>operator>></b></a> ( Q_UINT32 & i )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-gt-gt-7"><b>operator>></b></a> ( Q_LONG & i )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-gt-gt-8"><b>operator>></b></a> ( Q_ULONG & i )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-gt-gt-9"><b>operator>></b></a> ( float & f )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-gt-gt-a"><b>operator>></b></a> ( double & f )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-gt-gt-b"><b>operator>></b></a> ( char *& s )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-lt-lt"><b>operator<<</b></a> ( Q_INT8 i )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-lt-lt-2"><b>operator<<</b></a> ( Q_UINT8 i )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-lt-lt-3"><b>operator<<</b></a> ( Q_INT16 i )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-lt-lt-4"><b>operator<<</b></a> ( Q_UINT16 i )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-lt-lt-5"><b>operator<<</b></a> ( Q_INT32 i )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-lt-lt-6"><b>operator<<</b></a> ( Q_UINT32 i )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-lt-lt-7"><b>operator<<</b></a> ( Q_LONG i )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-lt-lt-8"><b>operator<<</b></a> ( Q_ULONG i )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-lt-lt-9"><b>operator<<</b></a> ( float f )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-lt-lt-a"><b>operator<<</b></a> ( double f )</div></li>
<li><div class=fn>QDataStream & <a href="#operator-lt-lt-b"><b>operator<<</b></a> ( const char * s )</div></li>
<li><div class=fn>QDataStream & <a href="#readBytes"><b>readBytes</b></a> ( char *& s, uint & l )</div></li>
<li><div class=fn>QDataStream & <a href="#readRawBytes"><b>readRawBytes</b></a> ( char * s, uint len )</div></li>
<li><div class=fn>QDataStream & <a href="#writeBytes"><b>writeBytes</b></a> ( const char * s, uint len )</div></li>
<li><div class=fn>QDataStream & <a href="#writeRawBytes"><b>writeRawBytes</b></a> ( const char * s, uint len )</div></li>
</ul>
<hr><a name="details"></a><h2>Detailed Description</h2>
<p> The QDataStream class provides serialization of
binary data to a <a href="qiodevice.html">QIODevice</a>.
<p>
<p> A data stream is a binary stream of encoded information which is 100%
independent of the host computer's operating system, CPU or byte
order. For example a data stream that is written by a PC under Windows
can be read by a Sun SPARC running Solaris.
<p> You can also use a data stream to read/write <a href="#raw">raw
unencoded binary data</a>. If you want a "parsing" input stream, see
<a href="qtextstream.html">QTextStream</a>.
<p> The QDataStream class implements serialization of primitive types, like
<tt>char</tt>, <tt>short</tt>, <tt>int</tt>, <tt>char*</tt> etc. Serialization of more complex
data is accomplished by breaking up the data into primitive units.
<p> A data stream cooperates closely with a QIODevice. A QIODevice
represents an input/output medium one can read data from and write data
to. The <a href="qfile.html">QFile</a> class is an example of an IO device.
<p> Example (write binary data to a stream):
<pre>
<a href="qfile.html">QFile</a> f( "file.dta" );
f.<a href="qfile.html#open">open</a>( <a href="qfile.html#open">IO_WriteOnly</a> );
QDataStream s( &f ); // we will serialize the data into file f
s << "the answer is"; // serialize a string
s << (Q_INT32)42; // serialize an integer
</pre>
<p> Example (read binary data from a stream):
<pre>
<a href="qfile.html">QFile</a> f( "file.dta" );
f.<a href="qfile.html#open">open</a>( <a href="qfile.html#open">IO_ReadOnly</a> );
QDataStream s( &f ); // read the data serialized from file f
<a href="qstring.html">QString</a> str;
Q_INT32 a;
s >> str >> a; // extract "the answer is" and 42
</pre>
<p> Each item written to the stream is written in a predefined binary
format that varies depending on the item's type. Supported Qt types
include <a href="qbrush.html">QBrush</a>, <a href="qcolor.html">QColor</a>, <a href="qdatetime.html">QDateTime</a>, <a href="qfont.html">QFont</a>, <a href="qpixmap.html">QPixmap</a>, <a href="qstring.html">QString</a>, <a href="qvariant.html">QVariant</a>
and many others. For the complete list of all Qt types supporting data
streaming see <a href="datastreamformat.html">Format of the QDataStream
operators</a> .
<p> To take one example, a <tt>char*</tt> string is written as a 32-bit integer
equal to the length of the string including the NUL byte, followed by
all the characters of the string including the NUL byte. When reading
a <tt>char*</tt> string, 4 bytes are read to create the 32-bit length value,
then that many characters for the <tt>char*</tt> string including the NUL
are read.
<p> The initial IODevice is usually set in the constructor, but can be
changed with <a href="#setDevice">setDevice</a>(). If you've reached the end of the data (or if
there is no IODevice set) <a href="#atEnd">atEnd</a>() will return TRUE.
<p> If you want the data to be compatible with an earlier version of Qt
use <a href="#setVersion">setVersion</a>().
<p> If you want the data to be human-readable, e.g. for debugging, you can
set the data stream into printable data mode with <a href="#setPrintableData">setPrintableData</a>().
The data is then written slower, in a bloated but human readable
format.
<p> If you are producing a new binary data format, such as a file format
for documents created by your application, you could use a QDataStream
to write the data in a portable format. Typically, you would write
a brief header containing a magic string and a version number to give
yourself room for future expansion. For example:
<p> <pre>
<a href="qfile.html">QFile</a> f( "file.xxx" );
f.<a href="qfile.html#open">open</a>( IO_WriteOnly );
QDataStream s( &f );
// Write a header with a "magic number" and a version
s << (Q_UINT32)0xa0b0c0d0;
s << (Q_INT32)123;
// Write the data
s << [lots of interesting data]
</pre>
<p> Then read it in with:
<p> <pre>
<a href="qfile.html">QFile</a> f( "file.xxx" );
f.<a href="qfile.html#open">open</a>( IO_ReadOnly );
QDataStream s( &f );
// Read and check the header
Q_UINT32 magic;
s >> magic;
if ( magic != 0xa0b0c0d0 )
return XXX_BAD_FILE_FORMAT;
// Read the version
Q_INT32 version;
s >> version;
if ( version < 100 )
return XXX_BAD_FILE_TOO_OLD;
if ( version > 123 )
return XXX_BAD_FILE_TOO_NEW;
if ( version <= 110 )
s.<a href="#setVersion">setVersion</a>(1);
// Read the data
s >> [lots of interesting data];
if ( version > 120 )
s >> [data new in XXX version 1.2];
s >> [other interesting data];
</pre>
<p> You can select which byte order to use when serializing data. The
default setting is big endian (MSB first). Changing it to little
endian breaks the portability (unless the reader also changes to
little endian). We recommend keeping this setting unless you have
special requirements.
<p> <b>Reading and writing raw binary data</b>
<a name="raw">
<p> You may wish to read/write your own raw binary data to/from the
data stream directly. Data may be read from the stream into a
preallocated char* using <a href="#readRawBytes">readRawBytes</a>(). Similarly data can be
written to the stream using <a href="#writeRawBytes">writeRawBytes</a>(). Notice that any
encoding/decoding of the data must be done by you.
<p> A similar pair of functions is <a href="#readBytes">readBytes</a>() and <a href="#writeBytes">writeBytes</a>(). These
differ from their <em>raw</em> counterparts as follows: readBytes() reads
a Q_UINT32 which is taken to be the length of the data to be read,
then that number of bytes is read into the preallocated char*;
writeBytes() writes a Q_UINT32 containing the length of the data,
followed by the data. Notice that any encoding/decoding of the data
(apart from the length Q_UINT32) must be done by you.
<p> <p>See also <a href="qtextstream.html">QTextStream</a>, <a href="qvariant.html">QVariant</a> and <a href="io.html">Input/Output and Networking</a>.
<hr><h2>Member Type Documentation</h2>
<h3 class=fn><a name="ByteOrder-enum"></a>QDataStream::ByteOrder</h3>
<p> The byte order used for reading/writing the data.
<ul>
<li><tt>QDataStream::BigEndian</tt> - the default
<li><tt>QDataStream::LittleEndian</tt>
</ul>
<hr><h2>Member Function Documentation</h2>
<h3 class=fn><a name="QDataStream"></a>QDataStream::QDataStream ()
</h3>
Constructs a data stream that has no IO device.
<p> <p>See also <a href="#setDevice">setDevice</a>().
<h3 class=fn><a name="QDataStream-2"></a>QDataStream::QDataStream ( <a href="qiodevice.html">QIODevice</a> * d )
</h3>
Constructs a data stream that uses the IO device <em>d</em>.
<p> <p>See also <a href="#setDevice">setDevice</a>() and <a href="#device">device</a>().
<h3 class=fn><a name="QDataStream-3"></a>QDataStream::QDataStream ( <a href="qbytearray.html">QByteArray</a> a, int mode )
</h3>
Constructs a data stream that operates on a byte array, <em>a</em>, through
an internal <a href="qbuffer.html">QBuffer</a> device. The <em>mode</em> is a <a href="qiodevice.html#mode">QIODevice::mode</a>(),
usually either <a href="qfile.html#open">IO_ReadOnly</a> or <a href="qfile.html#open">IO_WriteOnly</a>.
<p> Example:
<pre>
static char bindata[] = { 231, 1, 44, ... };
<a href="qbytearray.html">QByteArray</a> a;
a.<a href="qmemarray.html#setRawData">setRawData</a>( bindata, sizeof(bindata) ); // a points to bindata
QDataStream s( a, <a href="qfile.html#open">IO_ReadOnly</a> ); // open on a's data
s >> [something]; // read raw bindata
a.<a href="qmemarray.html#resetRawData">resetRawData</a>( bindata, sizeof(bindata) ); // finished
</pre>
<p> The <a href="qmemarray.html#setRawData">QByteArray::setRawData</a>() function is not for the inexperienced.
<h3 class=fn><a name="~QDataStream"></a>QDataStream::~QDataStream ()<tt> [virtual]</tt>
</h3>
Destroys the data stream.
<p> The destructor will not affect the current IO device, unless it
is an internal IO device processing a <a href="qbytearray.html">QByteArray</a> passed in the
<em>constructor</em>, in which case the internal IO device is destroyed.
<h3 class=fn>bool <a name="atEnd"></a>QDataStream::atEnd () const
</h3>
Returns TRUE if the IO device has reached the end position (end of the
stream or file) or if there is no IO device set; otherwise returns
FALSE, i.e. if the current position of the IO device is before the end
position.
<p> <p>See also <a href="qiodevice.html#atEnd">QIODevice::atEnd</a>().
<h3 class=fn>int <a name="byteOrder"></a>QDataStream::byteOrder () const
</h3>
Returns the current byte order setting -- either <a href="#ByteOrder-enum">BigEndian</a> or
<a href="#ByteOrder-enum">LittleEndian</a>.
<p> <p>See also <a href="#setByteOrder">setByteOrder</a>().
<h3 class=fn><a href="qiodevice.html">QIODevice</a> * <a name="device"></a>QDataStream::device () const
</h3>
Returns the IO device currently set.
<p>See also <a href="#setDevice">setDevice</a>() and <a href="#unsetDevice">unsetDevice</a>().
<h3 class=fn>bool <a name="eof"></a>QDataStream::eof () const
</h3>
<p> <b>This function is obsolete.</b> It is provided to keep old source working. We strongly advise against using it in new code.
<p> Returns TRUE if the IO device has reached the end position (end of
stream or file) or if there is no IO device set.
<p> Returns FALSE if the current position of the read/write head of the IO
device is somewhere before the end position.
<p> <p>See also <a href="qiodevice.html#atEnd">QIODevice::atEnd</a>().
<h3 class=fn>bool <a name="isPrintableData"></a>QDataStream::isPrintableData () const
</h3>
Returns TRUE if the printable data flag has been set.
<p>See also <a href="#setPrintableData">setPrintableData</a>().
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-lt-lt"></a>QDataStream::operator<< ( Q_INT8 i )
</h3>
Writes a signed byte, <em>i</em>, to the stream and returns a reference
to the stream.
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-lt-lt-2"></a>QDataStream::operator<< ( Q_UINT8 i )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Writes an unsigned byte, <em>i</em>, to the stream and returns a reference
to the stream.
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-lt-lt-3"></a>QDataStream::operator<< ( Q_INT16 i )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Writes a signed 16-bit integer, <em>i</em>, to the stream and returns a
reference to the stream.
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-lt-lt-4"></a>QDataStream::operator<< ( Q_UINT16 i )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Writes an unsigned 16-bit integer, <em>i</em>, to the stream and returns a
reference to the stream.
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-lt-lt-5"></a>QDataStream::operator<< ( Q_INT32 i )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Writes a signed 32-bit integer, <em>i</em>, to the stream and returns a
reference to the stream.
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-lt-lt-6"></a>QDataStream::operator<< ( Q_UINT32 i )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Writes an unsigned integer, <em>i</em>, to the stream as a 32-bit unsigned
integer (Q_UINT32). Returns a reference to the stream.
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-lt-lt-7"></a>QDataStream::operator<< ( Q_LONG i )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Writes a signed integer, <em>i</em>, of the system's word length to the
stream and returns a reference to the stream.
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-lt-lt-8"></a>QDataStream::operator<< ( Q_ULONG i )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Writes an unsigned integer, <em>i</em>, of the system's word length to the
stream and returns a reference to the stream.
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-lt-lt-9"></a>QDataStream::operator<< ( float f )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Writes a 32-bit floating point number, <em>f</em>, to the stream using the
standard IEEE754 format. Returns a reference to the stream.
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-lt-lt-a"></a>QDataStream::operator<< ( double f )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Writes a 64-bit floating point number, <em>f</em>, to the stream using the
standard IEEE754 format. Returns a reference to the stream.
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-lt-lt-b"></a>QDataStream::operator<< ( const char * s )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Writes the '\0'-terminated string <em>s</em> to the stream and returns
a reference to the stream.
<p> The string is serialized using <a href="#writeBytes">writeBytes</a>().
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-gt-gt"></a>QDataStream::operator>> ( Q_INT8 & i )
</h3>
Reads a signed byte from the stream into <em>i</em>, and returns a reference
to the stream.
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-gt-gt-2"></a>QDataStream::operator>> ( Q_UINT8 & i )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Reads an unsigned byte from the stream into <em>i</em>, and returns a
reference to the stream.
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-gt-gt-3"></a>QDataStream::operator>> ( Q_INT16 & i )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Reads a signed 16-bit integer from the stream into <em>i</em>, and returns a
reference to the stream.
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-gt-gt-4"></a>QDataStream::operator>> ( Q_UINT16 & i )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Reads an unsigned 16-bit integer from the stream into <em>i</em>, and returns
a reference to the stream.
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-gt-gt-5"></a>QDataStream::operator>> ( Q_INT32 & i )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Reads a signed 32-bit integer from the stream into <em>i</em>, and returns a
reference to the stream.
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-gt-gt-6"></a>QDataStream::operator>> ( Q_UINT32 & i )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Reads an unsigned 32-bit integer from the stream into <em>i</em>, and
returns a reference to the stream.
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-gt-gt-7"></a>QDataStream::operator>> ( Q_LONG & i )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Reads a signed integer of the system's word length
from the stream into <em>i</em>, and returns a reference to the stream.
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-gt-gt-8"></a>QDataStream::operator>> ( Q_ULONG & i )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Reads an unsigned integer of the system's word length from the stream,
into <em>i</em>, and returns a reference to the stream.
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-gt-gt-9"></a>QDataStream::operator>> ( float & f )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Reads a 32-bit floating point number from the stream into <em>f</em>, using
the standard IEEE754 format. Returns a reference to the stream.
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-gt-gt-a"></a>QDataStream::operator>> ( double & f )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Reads a 64-bit floating point number from the stream into <em>f</em>, using
the standard IEEE754 format. Returns a reference to the stream.
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-gt-gt-b"></a>QDataStream::operator>> ( char *& s )
</h3>
This is an overloaded member function, provided for convenience. It behaves essentially like the above function.
<p> Reads the '\0'-terminated string <em>s</em> from the stream and returns
a reference to the stream.
<p> Space for the string is allocated using <tt>new</tt> -- the caller must
destroy it with delete[].
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="readBytes"></a>QDataStream::readBytes ( char *& s, uint & l )
</h3>
Reads the buffer <em>s</em> from the stream and returns a reference to the
stream.
<p> The buffer <em>s</em> is allocated using <tt>new</tt>. Destroy it with the <tt>delete[]</tt>
operator. If the length is zero or <em>s</em> cannot be allocated, <em>s</em> is
set to 0.
<p> The <em>l</em> parameter will be set to the length of the buffer.
<p> The serialization format is a Q_UINT32 length specifier first, then <em>l</em> bytes of data. Note that the data is <em>not</em> encoded.
<p> <p>See also <a href="#readRawBytes">readRawBytes</a>() and <a href="#writeBytes">writeBytes</a>().
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="readRawBytes"></a>QDataStream::readRawBytes ( char * s, uint len )
</h3>
Reads <em>len</em> bytes from the stream into <em>s</em> and returns a reference to
the stream.
<p> The buffer <em>s</em> must be preallocated. The data is <em>not</em> encoded.
<p> <p>See also <a href="#readBytes">readBytes</a>(), <a href="qiodevice.html#readBlock">QIODevice::readBlock</a>() and <a href="#writeRawBytes">writeRawBytes</a>().
<h3 class=fn>void <a name="setByteOrder"></a>QDataStream::setByteOrder ( int bo )
</h3>
Sets the serialization byte order to <em>bo</em>.
<p> The <em>bo</em> parameter can be <a href="#ByteOrder-enum">QDataStream::BigEndian</a> or
<a href="#ByteOrder-enum">QDataStream::LittleEndian</a>.
<p> The default setting is big endian. We recommend leaving this setting
unless you have special requirements.
<p> <p>See also <a href="#byteOrder">byteOrder</a>().
<h3 class=fn>void <a name="setDevice"></a>QDataStream::setDevice ( <a href="qiodevice.html">QIODevice</a> * d )
</h3>
void <a href="#setDevice">QDataStream::setDevice</a>(<a href="qiodevice.html">QIODevice</a> *d )
Sets the IO device to <em>d</em>.
<p>See also <a href="#device">device</a>() and <a href="#unsetDevice">unsetDevice</a>().
<h3 class=fn>void <a name="setPrintableData"></a>QDataStream::setPrintableData ( bool enable )
</h3>
Sets (if <em>enable</em> is TRUE) or clears the printable data flag.
<p> If this flag is set, the write functions will generate output that
consists of printable characters (7 bit ASCII).
<p> We recommend enabling printable data only for debugging purposes
(it is slower and creates larger output).
<h3 class=fn>void <a name="setVersion"></a>QDataStream::setVersion ( int v )
</h3>
Sets the version number of the data serialization format.
<p> You don't need to set a version if you are using the current
version of Qt.
<p> In order to accommodate new functionality, the datastream
serialization format of some Qt classes has changed in some versions
of Qt. If you want to read data that was created by an earlier version
of Qt, or write data that can be read by a program that was compiled
with an earlier version of Qt, use this function to modify the
serialization format of QDataStream.
<p> <ul>
<li> For Qt 3.0 compatibility, use <em>v</em> == 4.
<li> For Qt 2.1.x and Qt 2.2.x compatibility, use <em>v</em> == 3.
<li> For Qt 2.0.x compatibility, use <em>v</em> == 2.
<li> For Qt 1.x compatibility, use <em>v</em> == 1.
</ul>
<p> <p>See also <a href="#version">version</a>().
<h3 class=fn>void <a name="unsetDevice"></a>QDataStream::unsetDevice ()
</h3>
Unsets the IO device. This is the same as calling <a href="#setDevice">setDevice</a>( 0 ).
<p>See also <a href="#device">device</a>() and <a href="#setDevice">setDevice</a>().
<h3 class=fn>int <a name="version"></a>QDataStream::version () const
</h3>
Returns the version number of the data serialization format.
In Qt 3.0, this number is 4.
<p>See also <a href="#setVersion">setVersion</a>().
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="writeBytes"></a>QDataStream::writeBytes ( const char * s, uint len )
</h3>
Writes the length specifier <em>len</em> and the buffer <em>s</em> to the stream and
returns a reference to the stream.
<p> The <em>len</em> is serialized as a Q_UINT32, followed by <em>len</em> bytes from
<em>s</em>. Note that the data is <em>not</em> encoded.
<p> <p>See also <a href="#writeRawBytes">writeRawBytes</a>() and <a href="#readBytes">readBytes</a>().
<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="writeRawBytes"></a>QDataStream::writeRawBytes ( const char * s, uint len )
</h3>
Writes <em>len</em> bytes from <em>s</em> to the stream and returns a reference to the
stream. The data is <em>not</em> encoded.
<p> <p>See also <a href="#writeBytes">writeBytes</a>(), <a href="qiodevice.html#writeBlock">QIODevice::writeBlock</a>() and <a href="#readRawBytes">readRawBytes</a>().
<!-- eof -->
<hr><p>
This file is part of the <a href="index.html">Qt toolkit</a>.
Copyright © 1995-2001
<a href="http://www.trolltech.com/">Trolltech</a>. All Rights Reserved.<p><address><hr><div align=center>
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<a href="http://www.trolltech.com">Trolltech</a><td><a href="http://www.trolltech.com/trademarks.html">Trademarks</a>
<td align=right><div align=right>Qt version 3.0.2</div>
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