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</style></head><body><table border="0" cellpadding="0" cellspacing="0" width="100%"><tr /><td align="left" valign="top" width="32"><img align="left" border="0" height="32" src="images/rb-logo.png" width="32" /></td><td width="1">  </td><td class="postheader" valign="center"><a href="index.html"><font color="#004faf">Home</font></a> · <a href="classes.html"><font color="#004faf">All Classes</font></a> · <a href="modules.html"><font color="#004faf">Modules</font></a></td></table><h1 align="center">QTemporaryFile Class Reference<br /><sup><sup>[<a href="qtcore.html">QtCore</a> module]</sup></sup></h1><p>The QTemporaryFile class is an I/O device that operates on
temporary files. <a href="#details">More...</a></p>
<p>Inherits <a href="qfile.html">QFile</a>.</p><h3>Methods</h3><ul><li><div class="fn" /><b><a href="qtemporaryfile.html#QTemporaryFile">__init__</a></b> (<i>self</i>)</li><li><div class="fn" /><b><a href="qtemporaryfile.html#QTemporaryFile-2">__init__</a></b> (<i>self</i>, QString <i>templateName</i>)</li><li><div class="fn" /><b><a href="qtemporaryfile.html#QTemporaryFile-3">__init__</a></b> (<i>self</i>, QObject <i>parent</i>)</li><li><div class="fn" /><b><a href="qtemporaryfile.html#QTemporaryFile-4">__init__</a></b> (<i>self</i>, QString <i>templateName</i>, QObject <i>parent</i>)</li><li><div class="fn" />bool <b><a href="qtemporaryfile.html#autoRemove">autoRemove</a></b> (<i>self</i>)</li><li><div class="fn" />QAbstractFileEngine <b><a href="qtemporaryfile.html#fileEngine">fileEngine</a></b> (<i>self</i>)</li><li><div class="fn" />QString <b><a href="qtemporaryfile.html#fileName">fileName</a></b> (<i>self</i>)</li><li><div class="fn" />QString <b><a href="qtemporaryfile.html#fileTemplate">fileTemplate</a></b> (<i>self</i>)</li><li><div class="fn" />bool <b><a href="qtemporaryfile.html#open">open</a></b> (<i>self</i>)</li><li><div class="fn" />bool <b><a href="qtemporaryfile.html#open-2">open</a></b> (<i>self</i>, QIODevice.OpenMode <i>flags</i>)</li><li><div class="fn" /><b><a href="qtemporaryfile.html#setAutoRemove">setAutoRemove</a></b> (<i>self</i>, bool <i>b</i>)</li><li><div class="fn" /><b><a href="qtemporaryfile.html#setFileTemplate">setFileTemplate</a></b> (<i>self</i>, QString <i>name</i>)</li></ul><h3>Static Methods</h3><ul><li><div class="fn" />QTemporaryFile <b><a href="qtemporaryfile.html#createLocalFile">createLocalFile</a></b> (QString <i>fileName</i>)</li><li><div class="fn" />QTemporaryFile <b><a href="qtemporaryfile.html#createLocalFile-2">createLocalFile</a></b> (QFile <i>file</i>)</li></ul><a name="details" /><hr /><h2>Detailed Description</h2><p>The QTemporaryFile class is an I/O device that operates on
temporary files.</p>
<p>QTemporaryFile is used to create unique temporary files safely.
The file itself is created by calling <a href="qtemporaryfile.html#open">open</a>(). The name of the temporary
file is guaranteed to be unique (i.e., you are guaranteed to not
overwrite an existing file), and the file will subsequently be
removed upon destruction of the QTemporaryFile object. This is an
important technique that avoids data corruption for applications
that store data in temporary files. The file name is either
auto-generated, or created based on a template, which is passed to
QTemporaryFile's constructor.</p>
<p>Example:</p>
<pre class="cpp">
<span class="comment">// Within a function/method...</span>
<span class="type">QTemporaryFile</span> file;
<span class="keyword">if</span> (file<span class="operator">.</span>open()) {
<span class="comment">// file.fileName() returns the unique file name</span>
}
<span class="comment">// The QTemporaryFile destructor removes the temporary file</span>
<span class="comment">// as it goes out of scope.</span>
</pre>
<p>Reopening a QTemporaryFile after calling <a href="qfile.html#close">close</a>() is safe. For as long as the
QTemporaryFile object itself is not destroyed, the unique temporary
file will exist and be kept open internally by QTemporaryFile.</p>
<p>The file name of the temporary file can be found by calling
<a href="qtemporaryfile.html#fileName">fileName</a>(). Note that
this is only defined after the file is first opened; the function
returns an empty string before this.</p>
<p>A temporary file will have some static part of the name and some
part that is calculated to be unique. The default filename
<tt>qt_temp</tt> will be placed into the temporary path as returned
by <a href="qdir.html#tempPath">QDir.tempPath</a>(). If you
specify your own filename, a relative file path will not be placed
in the temporary directory by default, but be relative to the
current working directory.</p>
<p>Specified filenames can contain the following template
<tt>XXXXXX</tt> (six upper case "X" characters), which will be
replaced by the auto-generated portion of the filename. Note that
the template is case sensitive. If the template is not present in
the filename, QTemporaryFile appends the generated part to the
filename given.</p>
<hr /><h2>Method Documentation</h2><h3 class="fn"><a name="QTemporaryFile" />QTemporaryFile.__init__ (<i>self</i>)</h3><p>Constructs a <a href="qtemporaryfile.html">QTemporaryFile</a> in
<a href="qdir.html#tempPath">QDir.tempPath</a>(), using the file
template "qt_temp.XXXXXX". The file is stored in the system's
temporary directory.</p>
<p><b>See also</b> <a href="qtemporaryfile.html#setFileTemplate">setFileTemplate</a>() and
<a href="qdir.html#tempPath">QDir.tempPath</a>().</p>
<h3 class="fn"><a name="QTemporaryFile-2" />QTemporaryFile.__init__ (<i>self</i>, QString <i>templateName</i>)</h3><p>Constructs a <a href="qtemporaryfile.html">QTemporaryFile</a>
with a template filename of <i>templateName</i>. Upon opening the
temporary file this will be used to create a unique filename.</p>
<p>If the <i>templateName</i> does not contain XXXXXX it will
automatically be appended and used as the dynamic portion of the
filename.</p>
<p>If <i>templateName</i> is a relative path, the path will be
relative to the current working directory. You can use <a href="qdir.html#tempPath">QDir.tempPath</a>() to construct
<i>templateName</i> if you want use the system's temporary
directory.</p>
<p><b>See also</b> <a href="qtemporaryfile.html#open">open</a>()
and <a href="qtemporaryfile.html#fileTemplate">fileTemplate</a>().</p>
<h3 class="fn"><a name="QTemporaryFile-3" />QTemporaryFile.__init__ (<i>self</i>, <a href="qobject.html">QObject</a> <i>parent</i>)</h3><p>The <i>parent</i> argument, if not None, causes <i>self</i> to be owned by Qt instead of PyQt.</p><p>Constructs a <a href="qtemporaryfile.html">QTemporaryFile</a>
(with the given <i>parent</i>) in <a href="qdir.html#tempPath">QDir.tempPath</a>(), using the file template
"qt_temp.XXXXXX".</p>
<p><b>See also</b> <a href="qtemporaryfile.html#setFileTemplate">setFileTemplate</a>().</p>
<h3 class="fn"><a name="QTemporaryFile-4" />QTemporaryFile.__init__ (<i>self</i>, QString <i>templateName</i>, <a href="qobject.html">QObject</a> <i>parent</i>)</h3><p>The <i>parent</i> argument, if not None, causes <i>self</i> to be owned by Qt instead of PyQt.</p><p>Constructs a <a href="qtemporaryfile.html">QTemporaryFile</a>
with a template filename of <i>templateName</i> and the specified
<i>parent</i>. Upon opening the temporary file this will be used to
create a unique filename.</p>
<p>If the <i>templateName</i> does not contain XXXXXX it will
automatically be appended and used as the dynamic portion of the
filename.</p>
<p>If <i>templateName</i> is a relative path, the path will be
relative to the current working directory. You can use <a href="qdir.html#tempPath">QDir.tempPath</a>() to construct
<i>templateName</i> if you want use the system's temporary
directory.</p>
<p><b>See also</b> <a href="qtemporaryfile.html#open">open</a>()
and <a href="qtemporaryfile.html#fileTemplate">fileTemplate</a>().</p>
<h3 class="fn"><a name="autoRemove" />bool QTemporaryFile.autoRemove (<i>self</i>)</h3><p>Returns true if the <a href="qtemporaryfile.html">QTemporaryFile</a> is in auto remove mode.
Auto-remove mode will automatically delete the filename from disk
upon destruction. This makes it very easy to create your <a href="qtemporaryfile.html">QTemporaryFile</a> object on the stack, fill
it with data, read from it, and finally on function return it will
automatically clean up after itself.</p>
<p>Auto-remove is on by default.</p>
<p><b>See also</b> <a href="qtemporaryfile.html#setAutoRemove">setAutoRemove</a>() and
<a href="qfile.html#remove">remove</a>().</p>
<h3 class="fn"><a name="createLocalFile" /><a href="qtemporaryfile.html">QTemporaryFile</a> QTemporaryFile.createLocalFile (QString <i>fileName</i>)</h3><p>If <i>file</i> is not on a local disk, a temporary file is
created on a local disk, <i>file</i> is copied into the temporary
local file, and a pointer to the temporary local file is returned.
If <i>file</i> is already on a local disk, a copy is not created
and 0 is returned.</p>
<h3 class="fn"><a name="createLocalFile-2" /><a href="qtemporaryfile.html">QTemporaryFile</a> QTemporaryFile.createLocalFile (<a href="qfile.html">QFile</a> <i>file</i>)</h3><p>This is an overloaded function.</p>
<p>Works on the given <i>fileName</i> rather than an existing
<a href="qfile.html">QFile</a> object.</p>
<h3 class="fn"><a name="fileEngine" /><a href="qabstractfileengine.html">QAbstractFileEngine</a> QTemporaryFile.fileEngine (<i>self</i>)</h3><h3 class="fn"><a name="fileName" />QString QTemporaryFile.fileName (<i>self</i>)</h3><p>Returns the complete unique filename backing the <a href="qtemporaryfile.html">QTemporaryFile</a> object. This string is
null before the <a href="qtemporaryfile.html">QTemporaryFile</a> is
opened, afterwards it will contain the <a href="qtemporaryfile.html#fileTemplate">fileTemplate</a>() plus
additional characters to make it unique.</p>
<p><b>See also</b> <a href="qtemporaryfile.html#fileTemplate">fileTemplate</a>().</p>
<h3 class="fn"><a name="fileTemplate" />QString QTemporaryFile.fileTemplate (<i>self</i>)</h3><p>Returns the set file template. The default file template will be
called qt_temp and be placed in <a href="qdir.html#tempPath">QDir.tempPath</a>().</p>
<p><b>See also</b> <a href="qtemporaryfile.html#setFileTemplate">setFileTemplate</a>().</p>
<h3 class="fn"><a name="open" />bool QTemporaryFile.open (<i>self</i>)</h3><p>A <a href="qtemporaryfile.html">QTemporaryFile</a> will always
be opened in <a href="qiodevice.html#OpenModeFlag-enum">QIODevice.ReadWrite</a> mode,
this allows easy access to the data in the file. This function will
return true upon success and will set the <a href="qtemporaryfile.html#fileName">fileName</a>() to the unique
filename used.</p>
<p><b>See also</b> <a href="qtemporaryfile.html#fileName">fileName</a>().</p>
<h3 class="fn"><a name="open-2" />bool QTemporaryFile.open (<i>self</i>, <a href="qiodevice-openmode.html">QIODevice.OpenMode</a> <i>flags</i>)</h3><p>Reimplemented from <a href="qiodevice.html#open">QIODevice.open</a>().</p>
<p>Creates a unique file name for the temporary file, and opens it.
You can get the unique name later by calling <a href="qtemporaryfile.html#fileName">fileName</a>(). The file is
guaranteed to have been created by this function (i.e., it has
never existed before).</p>
<h3 class="fn"><a name="setAutoRemove" />QTemporaryFile.setAutoRemove (<i>self</i>, bool <i>b</i>)</h3><p>Sets the <a href="qtemporaryfile.html">QTemporaryFile</a> into
auto-remove mode if <i>b</i> is true.</p>
<p>Auto-remove is on by default.</p>
<p><b>See also</b> <a href="qtemporaryfile.html#autoRemove">autoRemove</a>() and <a href="qfile.html#remove">remove</a>().</p>
<h3 class="fn"><a name="setFileTemplate" />QTemporaryFile.setFileTemplate (<i>self</i>, QString <i>name</i>)</h3><p>Sets the static portion of the file name to <i>name</i>. If the
file template ends in XXXXXX that will automatically be replaced
with the unique part of the filename, otherwise a filename will be
determined automatically based on the static portion specified.</p>
<p>If <i>name</i> contains a relative file path, the path will be
relative to the current working directory. You can use <a href="qdir.html#tempPath">QDir.tempPath</a>() to construct <i>name</i>
if you want use the system's temporary directory.</p>
<p><b>See also</b> <a href="qtemporaryfile.html#fileTemplate">fileTemplate</a>().</p>
<address><hr /><div align="center"><table border="0" cellspacing="0" width="100%"><tr class="address"><td align="left" width="25%">PyQt 4.10.3 for X11</td><td align="center" width="50%">Copyright © <a href="http://www.riverbankcomputing.com">Riverbank Computing Ltd</a> and <a href="http://www.qtsoftware.com">Nokia</a> 2012</td><td align="right" width="25%">Qt 4.8.5</td></tr></table></div></address></body></html>
