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<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"><title>gio.InputStream</title><link rel="stylesheet" type="text/css" href="style.css"><meta name="generator" content="DocBook XSL Stylesheets V1.76.1"><link rel="home" href="index.html" title="PyGObject Reference Manual"><link rel="up" href="gio-class-reference.html" title="PyGio Class Reference"><link rel="prev" href="class-gioicon.html" title="gio.Icon"><link rel="next" href="class-gioloadableicon.html" title="gio.LoadableIcon"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">gio.InputStream</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="class-gioicon.html">Prev</a> </td><th width="60%" align="center">PyGio Class Reference</th><td width="20%" align="right"> <a accesskey="n" href="class-gioloadableicon.html">Next</a></td></tr></table><hr></div><div class="refentry" title="gio.InputStream"><a name="class-gioinputstream"></a><div class="titlepage"></div><div class="refnamediv"><h2>gio.InputStream</h2><p>gio.InputStream — Base class for implementing streaming input</p></div><div class="refsect1" title="Synopsis"><a name="id738986"></a><h2>Synopsis</h2><table bgcolor="#D0E0F0" width="100%"><tr><td><pre class="classsynopsis">class <span class="ooclass"><span class="classname">gio.InputStream</span></span>(<span class="ooclass"><span class="classname"><a class="link" href="class-gobject.html" title="gobject.GObject">gobject.GObject</a></span></span>):
<code class="methodsynopsis"> def <span class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--clear-pending" title="gio.InputStream.clear_pending">clear_pending</a></span>(<span class="methodparam"></span>)</code><br><code class="methodsynopsis"> def <span class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--close" title="gio.InputStream.close">close</a></span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>cancellable</code></strong></span><span class="initializer">=None</span></span>)</code><br><code class="methodsynopsis"> def <span class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--close-async" title="gio.InputStream.close_async">close_async</a></span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>callback</code></strong></span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>io_priority</code></strong></span><span class="initializer">=glib.PRIORITY_DEFAULT</span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>cancellable</code></strong></span><span class="initializer">=None</span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>user_data</code></strong></span><span class="initializer">=None</span></span>)</code><br><code class="methodsynopsis"> def <span class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--close-finish" title="gio.InputStream.close_finish">close_finish</a></span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>result</code></strong></span></span>)</code><br><code class="methodsynopsis"> def <span class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--has-pending" title="gio.InputStream.has_pending">has_pending</a></span>(<span class="methodparam"></span>)</code><br><code class="methodsynopsis"> def <span class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--is-closed" title="gio.InputStream.is_closed">is_closed</a></span>(<span class="methodparam"></span>)</code><br><code class="methodsynopsis"> def <span class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--read" title="gio.InputStream.read">read</a></span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>count</code></strong></span><span class="initializer">=-1</span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>cancellable</code></strong></span><span class="initializer">=None</span></span>)</code><br><code class="methodsynopsis"> def <span class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--read-async" title="gio.InputStream.read_async">read_async</a></span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>count</code></strong></span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>callback</code></strong></span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>io_priority</code></strong></span><span class="initializer">=glib.PRIORITY_DEFAULT</span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>cancellable</code></strong></span><span class="initializer">=None</span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>user_data</code></strong></span><span class="initializer">=None</span></span>)</code><br><code class="methodsynopsis"> def <span class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--read-finish" title="gio.InputStream.read_finish">read_finish</a></span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>result</code></strong></span></span>)</code><br><code class="methodsynopsis"> def <span class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--read-part" title="gio.InputStream.read_part">read_part</a></span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>count</code></strong></span><span class="initializer">=-1</span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>cancellable</code></strong></span><span class="initializer">=None</span></span>)</code><br><code class="methodsynopsis"> def <span class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--set-pending" title="gio.InputStream.set_pending">set_pending</a></span>(<span class="methodparam"></span>)</code><br><code class="methodsynopsis"> def <span class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--skip" title="gio.InputStream.skip">skip</a></span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>count</code></strong></span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>cancellable</code></strong></span><span class="initializer">=None</span></span>)</code><br><code class="methodsynopsis"> def <span class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--skip-async" title="gio.InputStream.skip_async">skip_async</a></span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>count</code></strong></span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>callback</code></strong></span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>io_priority</code></strong></span><span class="initializer">=glib.PRIORITY_DEFAULT</span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>cancellable</code></strong></span><span class="initializer">=None</span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>user_data</code></strong></span><span class="initializer">=None</span></span>)</code><br><code class="methodsynopsis"> def <span class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--skip-finish" title="gio.InputStream.skip_finish">skip_finish</a></span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>result</code></strong></span></span>)</code><br></pre></td></tr></table></div><div class="refsect1" title="Ancestry"><a name="id739523"></a><h2>Ancestry</h2><pre class="synopsis">+-- <a class="link" href="class-gobject.html" title="gobject.GObject">gobject.GObject</a>
+-- <a class="link" href="class-gioinputstream.html" title="gio.InputStream">gio.InputStream</a>
</pre></div><div class="refsect1" title="Description"><a name="id739545"></a><h2>Description</h2><p>
<a class="link" href="class-gioinputstream.html" title="gio.InputStream"><code class="classname">gio.InputStream</code></a>
has functions to read from a stream (
<code class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--read" title="gio.InputStream.read">gio.InputStream.read</a></code>()
), to close a stream (
<code class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--close" title="gio.InputStream.close">gio.InputStream.close</a></code>()
) and to skip some content (
<code class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--skip" title="gio.InputStream.skip">gio.InputStream.skip</a></code>()
).
</p><p>
To copy the content of an input stream to an output stream without manually
handling the reads and writes, use
<code class="methodname"><PYGTKDOCLINK HREF="method-giooutputstream--skip">gio.OutputStream.splice</PYGTKDOCLINK></code>().
</p><p>
All of these functions have async variants too.
</p></div><div class="refsect1" title="Methods"><a name="id739593"></a><h2>Methods</h2><div class="refsect2" title="gio.InputStream.clear_pending"><a name="method-gioinputstream--clear-pending"></a><h3>gio.InputStream.clear_pending</h3><pre class="programlisting"><code class="methodsynopsis"> def <span class="methodname">clear_pending</span>(<span class="methodparam"></span>)</code></pre><table border="0" width="100%" bgcolor="#FFECCE"><col align="left" valign="top" width="0*"><tbody></tbody></table><p>
The <code class="methodname">clear_pending</code>() method clears the pending flag on stream.
</p></div><div class="refsect2" title="gio.InputStream.close"><a name="method-gioinputstream--close"></a><h3>gio.InputStream.close</h3><pre class="programlisting"><code class="methodsynopsis"> def <span class="methodname">close</span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>cancellable</code></strong></span><span class="initializer">=None</span></span>)</code></pre><table border="0" width="100%" bgcolor="#FFECCE"><col align="left" valign="top" width="0*"><tbody><tr><td><p><span class="term"><strong class="parameter"><code>cancellable</code></strong> :</span></p></td><td>optional
<a class="link" href="class-giocancellable.html" title="gio.Cancellable"><code class="classname">gio.Cancellable</code></a>
object, <code class="literal">None</code> to ignore.
</td></tr><tr><td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td><td><code class="literal">True</code> on success
<code class="literal">False</code> on failure.
</td></tr></tbody></table><p>
The <code class="methodname">close</code>() method closes the stream, releasing
resources related to it.
</p><p>
Once the stream is closed, all other operations will return gio.ERROR_CLOSED.
Closing a stream multiple times will not return an error.
</p><p>
Streams will be automatically closed when the last reference is dropped, but
you might want to call this function to make sure resources are released as
early as possible.
</p><p>
Some streams might keep the backing store of the stream (e.g. a file descriptor)
open after the stream is closed. See the documentation for the individual
stream for details.
</p><p>
On failure the first error that happened will be reported, but the close operation
will finish as much as possible. A stream that failed to close will still return
gio.ERROR_CLOSED for all operations. Still, it is important to check and report
the error to the user.
</p><p>
If cancellable is not <code class="literal">None</code>, then the operation can be cancelled by
triggering the cancellable object from another thread. If the operation was cancelled,
the error gio.ERROR_CANCELLED will be returned. Cancelling a close will still leave
the stream closed, but some streams can use a faster close that doesn't block to e.g.
check errors.
</p></div><div class="refsect2" title="gio.InputStream.close_async"><a name="method-gioinputstream--close-async"></a><h3>gio.InputStream.close_async</h3><pre class="programlisting"><code class="methodsynopsis"> def <span class="methodname">close_async</span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>callback</code></strong></span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>io_priority</code></strong></span><span class="initializer">=glib.PRIORITY_DEFAULT</span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>cancellable</code></strong></span><span class="initializer">=None</span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>user_data</code></strong></span><span class="initializer">=None</span></span>)</code></pre><table border="0" width="100%" bgcolor="#FFECCE"><col align="left" valign="top" width="0*"><tbody><tr><td><p><span class="term"><em class="parameter"><code>callback</code></em> :</span></p></td><td>a GAsyncReadyCallback to call when the request is satisfied.
</td></tr><tr><td><p><span class="term"><em class="parameter"><code>io_priority</code></em> :</span></p></td><td>the
<a class="xref" href="glib-constants.html#glib-priority-constants" title="Glib Priority Constants">Glib Priority Constants</a>
of the request.
</td></tr><tr><td><p><span class="term"><em class="parameter"><code>cancellable</code></em> :</span></p></td><td>optional
<a class="link" href="class-giocancellable.html" title="gio.Cancellable"><code class="classname">gio.Cancellable</code></a>
object, <code class="literal">None</code> to ignore.</td></tr><tr><td><p><span class="term"><em class="parameter"><code>user_data</code></em> :</span></p></td><td>the data to pass to callback function.
</td></tr></tbody></table><p>
The <code class="methodname">close_async</code>() method asynchronously requests an
asynchronous closes of the stream, releasing resources related to it.
</p><p>
For more details, see
<code class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--close" title="gio.InputStream.close">gio.InputStream.close</a></code>()
which is the synchronous version of this call.
</p><p>
When the operation is finished, callback will be called. You can then call
<code class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--close-finish" title="gio.InputStream.close_finish">gio.InputStream.close_finish</a></code>()
to get the result of the operation.
</p></div><div class="refsect2" title="gio.InputStream.close_finish"><a name="method-gioinputstream--close-finish"></a><h3>gio.InputStream.close_finish</h3><pre class="programlisting"><code class="methodsynopsis"> def <span class="methodname">close_finish</span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>result</code></strong></span></span>)</code></pre><table border="0" width="100%" bgcolor="#FFECCE"><col align="left" valign="top" width="0*"><tbody><tr><td><p><span class="term"><strong class="parameter"><code>result</code></strong> :</span></p></td><td>a <a class="link" href="class-gioasyncresult.html" title="gio.AsyncResult"><code class="classname">gio.AsyncResult</code></a>.
</td></tr><tr><td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td><td><code class="literal">True</code> if the stream was closed successfully.
</td></tr></tbody></table><p>
The <code class="methodname">close_finish</code>() method finishes an asynchronous
file append operation started with
<code class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--close-async" title="gio.InputStream.close_async">gio.InputStream.close_async</a></code>().
</p></div><div class="refsect2" title="gio.InputStream.has_pending"><a name="method-gioinputstream--has-pending"></a><h3>gio.InputStream.has_pending</h3><pre class="programlisting"><code class="methodsynopsis"> def <span class="methodname">has_pending</span>(<span class="methodparam"></span>)</code></pre><table border="0" width="100%" bgcolor="#FFECCE"><col align="left" valign="top" width="0*"><tbody><tr><td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td><td><code class="literal">True</code> if stream has pending actions.
</td></tr></tbody></table><p>
The <code class="methodname">has_pending</code>() method checks if an input stream has pending actions.
</p></div><div class="refsect2" title="gio.InputStream.is_closed"><a name="method-gioinputstream--is-closed"></a><h3>gio.InputStream.is_closed</h3><pre class="programlisting"><code class="methodsynopsis"> def <span class="methodname">is_closed</span>(<span class="methodparam"></span>)</code></pre><table border="0" width="100%" bgcolor="#FFECCE"><col align="left" valign="top" width="0*"><tbody><tr><td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td><td><code class="literal">True</code> if the stream is closed.
</td></tr></tbody></table><p>
The <code class="methodname">is_closed</code>() method checks if an input stream is closed.
</p></div><div class="refsect2" title="gio.InputStream.read"><a name="method-gioinputstream--read"></a><h3>gio.InputStream.read</h3><pre class="programlisting"><code class="methodsynopsis"> def <span class="methodname">read</span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>count</code></strong></span><span class="initializer">=-1</span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>cancellable</code></strong></span><span class="initializer">=None</span></span>)</code></pre><table border="0" width="100%" bgcolor="#FFECCE"><col align="left" valign="top" width="0*"><tbody><tr><td><p><span class="term"><strong class="parameter"><code>count</code></strong> :</span></p></td><td>optionally the number of bytes that will be read from the stream.
</td></tr><tr><td><p><span class="term"><strong class="parameter"><code>cancellable</code></strong> :</span></p></td><td>optional
<a class="link" href="class-giocancellable.html" title="gio.Cancellable"><code class="classname">gio.Cancellable</code></a>
object, <code class="literal">None</code> to ignore.
</td></tr><tr><td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td><td>The number of bytes read, or -1 on error.
</td></tr></tbody></table><p>
The <code class="methodname">read</code>() method tries to read count bytes from
the stream into the buffer starting at buffer. Will block during this read.
</p><p>
This function is similar to
<code class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--read-part" title="gio.InputStream.read_part">gio.InputStream.read_part</a></code>(),
except it tries to read as many bytes as requested, only stopping on an error or end of stream.
</p><p>
On a successful read of count bytes, or if we reached the end of the stream,
<code class="literal">True</code> is returned, and bytes_read is set to the number of bytes read into buffer.
</p><p>
If cancellable is not <code class="literal">None</code>, then the operation can be cancelled by
triggering the cancellable object from another thread. If the operation was cancelled,
the error gio.ERROR_CANCELLED will be returned. Cancelling a close will still leave
the stream closed, but some streams can use a faster close that doesn't block to e.g.
check errors.
</p><p>
If there is an error during the operation <code class="literal">False</code> is returned and error
is set to indicate the error status, bytes_read is updated to contain the number of
bytes read into buffer before the error occurred.
</p></div><div class="refsect2" title="gio.InputStream.read_async"><a name="method-gioinputstream--read-async"></a><h3>gio.InputStream.read_async</h3><pre class="programlisting"><code class="methodsynopsis"> def <span class="methodname">read_async</span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>count</code></strong></span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>callback</code></strong></span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>io_priority</code></strong></span><span class="initializer">=glib.PRIORITY_DEFAULT</span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>cancellable</code></strong></span><span class="initializer">=None</span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>user_data</code></strong></span><span class="initializer">=None</span></span>)</code></pre><table border="0" width="100%" bgcolor="#FFECCE"><col align="left" valign="top" width="0*"><tbody><tr><td><p><span class="term"><em class="parameter"><code>count</code></em> :</span></p></td><td>the number of bytes that will be read from the stream.
</td></tr><tr><td><p><span class="term"><em class="parameter"><code>callback</code></em> :</span></p></td><td>a GAsyncReadyCallback to call when the request is satisfied.
</td></tr><tr><td><p><span class="term"><em class="parameter"><code>io_priority</code></em> :</span></p></td><td>the
<a class="xref" href="glib-constants.html#glib-priority-constants" title="Glib Priority Constants">Glib Priority Constants</a>
of the request.
</td></tr><tr><td><p><span class="term"><em class="parameter"><code>cancellable</code></em> :</span></p></td><td>optional
<a class="link" href="class-giocancellable.html" title="gio.Cancellable"><code class="classname">gio.Cancellable</code></a>
object, <code class="literal">None</code> to ignore.</td></tr><tr><td><p><span class="term"><em class="parameter"><code>user_data</code></em> :</span></p></td><td>the data to pass to callback function.
</td></tr></tbody></table><p>
The <code class="methodname">read_async</code>() method requests an asynchronous read
of count bytes from the stream into the buffer.
</p><p>
For more details, see
<code class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--read" title="gio.InputStream.read">gio.InputStream.read</a></code>()
which is the synchronous version of this call.
</p><p>
When the operation is finished, callback will be called. You can then call
<code class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--read-finish" title="gio.InputStream.read_finish">gio.InputStream.read_finish</a></code>()
to get the result of the operation.
</p><p>
During an async request no other sync and async calls are allowed, and
will result in gio.ERROR_PENDING errors.
</p><p>
A value of count larger than G_MAXSSIZE will cause a gio.ERROR_INVALID_ARGUMENT error.
</p><p>
On success, the number of bytes read into the buffer will be passed to the callback.
It is not an error if this is not the same as the requested size, as it can happen e.g.
near the end of a file, but generally we try to read as many bytes as requested. Zero
is returned on end of file (or if count is zero), but never otherwise.
</p><p>
Any outstanding i/o request with higher priority (lower numerical value) will be
executed before an outstanding request with lower priority. Default priority is glib.PRIORITY_DEFAULT.
</p><p>
The asyncronous methods have a default fallback that uses threads to implement asynchronicity, so
they are optional for inheriting classes. However, if you override one you must override all.
</p></div><div class="refsect2" title="gio.InputStream.read_finish"><a name="method-gioinputstream--read-finish"></a><h3>gio.InputStream.read_finish</h3><pre class="programlisting"><code class="methodsynopsis"> def <span class="methodname">read_finish</span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>result</code></strong></span></span>)</code></pre><table border="0" width="100%" bgcolor="#FFECCE"><col align="left" valign="top" width="0*"><tbody><tr><td><p><span class="term"><strong class="parameter"><code>result</code></strong> :</span></p></td><td>a <a class="link" href="class-gioasyncresult.html" title="gio.AsyncResult"><code class="classname">gio.AsyncResult</code></a>.
</td></tr><tr><td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td><td>The number of bytes read in, or -1 on error.
</td></tr></tbody></table><p>
The <code class="methodname">read_finish</code>() method finishes an asynchronous
stream read operation started by
<code class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--read-async" title="gio.InputStream.read_async">gio.InputStream.read_async</a></code>().
</p></div><div class="refsect2" title="gio.InputStream.read_part"><a name="method-gioinputstream--read-part"></a><h3>gio.InputStream.read_part</h3><pre class="programlisting"><code class="methodsynopsis"> def <span class="methodname">read_part</span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>count</code></strong></span><span class="initializer">=-1</span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>cancellable</code></strong></span><span class="initializer">=None</span></span>)</code></pre><table border="0" width="100%" bgcolor="#FFECCE"><col align="left" valign="top" width="0*"><tbody><tr><td><p><span class="term"><strong class="parameter"><code>count</code></strong> :</span></p></td><td>optionally the number of bytes that will be read from the stream.
</td></tr><tr><td><p><span class="term"><strong class="parameter"><code>cancellable</code></strong> :</span></p></td><td>optional
<a class="link" href="class-giocancellable.html" title="gio.Cancellable"><code class="classname">gio.Cancellable</code></a>
object, <code class="literal">None</code> to ignore.
</td></tr><tr><td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td><td>The number of bytes read, or -1 on error.
</td></tr></tbody></table><p>
The <code class="methodname">read_part</code>() method tries to read count bytes from
the stream into the buffer starting at buffer. Will block during this read.
</p><p>
If count is zero returns zero and does nothing. A value of count larger than
G_MAXSSIZE will cause a gio.ERROR_INVALID_ARGUMENT error.
</p><p>
On success, the number of bytes read into the buffer is returned. It is
not an error if this is not the same as the requested size, as it can
happen e.g. near the end of a file. Zero is returned on end of file
(or if count is zero), but never otherwise.
</p><p>
If cancellable is not <code class="literal">None</code>, then the operation can be cancelled by
triggering the cancellable object from another thread. If the operation was cancelled,
the error gio.ERROR_CANCELLED will be returned. Cancelling a close will still leave
the stream closed, but some streams can use a faster close that doesn't block to e.g.
check errors.
</p><p>
On error -1 is returned and error is set accordingly.
</p><div class="note" title="Note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3>
This method roughly corresponds to C GIO g_input_stream_read.
</div></div><div class="refsect2" title="gio.InputStream.set_pending"><a name="method-gioinputstream--set-pending"></a><h3>gio.InputStream.set_pending</h3><pre class="programlisting"><code class="methodsynopsis"> def <span class="methodname">set_pending</span>(<span class="methodparam"></span>)</code></pre><table border="0" width="100%" bgcolor="#FFECCE"><col align="left" valign="top" width="0*"><tbody><tr><td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td><td><code class="literal">True</code> if pending was previously
unset and is now set.
</td></tr></tbody></table><p>
The <code class="methodname">set_pending</code>() method sets stream to have actions pending.
If the pending flag is already set or stream is closed,
it will return <code class="literal">False</code> and set error.
</p></div><div class="refsect2" title="gio.InputStream.skip"><a name="method-gioinputstream--skip"></a><h3>gio.InputStream.skip</h3><pre class="programlisting"><code class="methodsynopsis"> def <span class="methodname">skip</span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>count</code></strong></span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>cancellable</code></strong></span><span class="initializer">=None</span></span>)</code></pre><table border="0" width="100%" bgcolor="#FFECCE"><col align="left" valign="top" width="0*"><tbody><tr><td><p><span class="term"><strong class="parameter"><code>count</code></strong> :</span></p></td><td>the number of bytes that will be skipped from the stream.
</td></tr><tr><td><p><span class="term"><strong class="parameter"><code>cancellable</code></strong> :</span></p></td><td>optional
<a class="link" href="class-giocancellable.html" title="gio.Cancellable"><code class="classname">gio.Cancellable</code></a>
object, <code class="literal">None</code> to ignore.
</td></tr><tr><td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td><td>The number of bytes skipped, or -1 on error
</td></tr></tbody></table><p>
The <code class="methodname">skip</code>() method tries to skip count bytes
from the stream. Will block during the operation.
</p><p>
This is identical to
<code class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--read" title="gio.InputStream.read">read</a></code>(),
from a behaviour standpoint, but the bytes that are skipped are not
returned to the user. Some streams have an implementation that is more
efficient than reading the data.
</p><p>
This function is optional for inherited classes, as the default implementation emulates it using read.
</p><p>
If cancellable is not <code class="literal">None</code>, then the operation can be cancelled by
triggering the cancellable object from another thskip. If the operation was cancelled,
the error gio.ERROR_CANCELLED will be returned. Cancelling a close will still leave
the stream closed, but some streams can use a faster close that doesn't block to e.g.
check errors.
</p></div><div class="refsect2" title="gio.InputStream.skip_async"><a name="method-gioinputstream--skip-async"></a><h3>gio.InputStream.skip_async</h3><pre class="programlisting"><code class="methodsynopsis"> def <span class="methodname">skip_async</span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>count</code></strong></span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>callback</code></strong></span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>io_priority</code></strong></span><span class="initializer">=glib.PRIORITY_DEFAULT</span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>cancellable</code></strong></span><span class="initializer">=None</span></span>, <span class="methodparam"><span class="parameter"><strong class="parameter"><code>user_data</code></strong></span><span class="initializer">=None</span></span>)</code></pre><table border="0" width="100%" bgcolor="#FFECCE"><col align="left" valign="top" width="0*"><tbody><tr><td><p><span class="term"><em class="parameter"><code>count</code></em> :</span></p></td><td>the number of bytes that will be skipped from the stream.
</td></tr><tr><td><p><span class="term"><em class="parameter"><code>callback</code></em> :</span></p></td><td>a GAsyncskipyCallback to call when the request is satisfied.
</td></tr><tr><td><p><span class="term"><em class="parameter"><code>io_priority</code></em> :</span></p></td><td>the
<a class="xref" href="glib-constants.html#glib-priority-constants" title="Glib Priority Constants">Glib Priority Constants</a>
of the request.
</td></tr><tr><td><p><span class="term"><em class="parameter"><code>cancellable</code></em> :</span></p></td><td>optional
<a class="link" href="class-giocancellable.html" title="gio.Cancellable"><code class="classname">gio.Cancellable</code></a>
object, <code class="literal">None</code> to ignore.</td></tr><tr><td><p><span class="term"><em class="parameter"><code>user_data</code></em> :</span></p></td><td>the data to pass to callback function.
</td></tr></tbody></table><p>
The <code class="methodname">skip_async</code>() method request an asynchronous
skip of count bytes from the stream.
</p><p>
For more details, see
<code class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--skip" title="gio.InputStream.skip">gio.InputStream.skip</a></code>()
which is the synchronous version of this call.
</p><p>
When the operation is finished, callback will be called. You can then call
<code class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--skip-finish" title="gio.InputStream.skip_finish">gio.InputStream.skip_finish</a></code>()
to get the result of the operation.
</p><p>
During an async request no other sync and async calls are allowed, and
will result in gio.ERROR_PENDING errors.
</p><p>
A value of count larger than G_MAXSSIZE will cause a gio.ERROR_INVALID_ARGUMENT error.
</p><p>
On success, the number of bytes skipped will be passed to the callback. It is
not an error if this is not the same as the requested size, as it can happen
e.g. near the end of a file, but generally we try to skip as many bytes as requested.
Zero is returned on end of file (or if count is zero), but never otherwise.
</p><p>
Any outstanding i/o request with higher priority (lower numerical value) will be
executed before an outstanding request with lower priority. Default priority is glib.PRIORITY_DEFAULT.
</p><p>
The asyncronous methods have a default fallback that uses thskips to implement asynchronicity, so
they are optional for inheriting classes. However, if you override one you must override all.
</p></div><div class="refsect2" title="gio.InputStream.skip_finish"><a name="method-gioinputstream--skip-finish"></a><h3>gio.InputStream.skip_finish</h3><pre class="programlisting"><code class="methodsynopsis"> def <span class="methodname">skip_finish</span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>result</code></strong></span></span>)</code></pre><table border="0" width="100%" bgcolor="#FFECCE"><col align="left" valign="top" width="0*"><tbody><tr><td><p><span class="term"><strong class="parameter"><code>result</code></strong> :</span></p></td><td>a <a class="link" href="class-gioasyncresult.html" title="gio.AsyncResult"><code class="classname">gio.AsyncResult</code></a>.
</td></tr><tr><td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td><td>The number of bytes skipped in, or -1 on error.
</td></tr></tbody></table><p>
The <code class="methodname">skip_finish</code>() method finishes an asynchronous
stream skip operation started by
<code class="methodname"><a class="link" href="class-gioinputstream.html#method-gioinputstream--skip-async" title="gio.InputStream.skip_async">gio.InputStream.skip_async</a></code>().
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