docs/html/class-giobufferedinputstream.html

   1 <html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"><title>gio.BufferedInputStream</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-gioasyncresult.html" title="gio.AsyncResult"><link rel="next" href="class-giobufferedoutputstream.html" title="gio.BufferedOutputStream"></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.BufferedInputStream</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="class-gioasyncresult.html">Prev</a> </td><th width="60%" align="center">PyGio Class Reference</th><td width="20%" align="right"> <a accesskey="n" href="class-giobufferedoutputstream.html">Next</a></td></tr></table><hr></div><div class="refentry" title="gio.BufferedInputStream"><a name="class-giobufferedinputstream"></a><div class="titlepage"></div><div class="refnamediv"><h2>gio.BufferedInputStream</h2><p>gio.BufferedInputStream — Buffered Input Stream</p></div><div class="refsect1" title="Synopsis"><a name="id449200"></a><h2>Synopsis</h2><table bgcolor="#D0E0F0" width="100%"><tr><td><pre class="classsynopsis">class <span class="ooclass"><span class="classname">gio.BufferedInputStream</span></span>(<span class="ooclass"><span class="classname"><a class="link" href="class-giofilterinputstream.html" title="gio.FilterInputStream">gio.FilterInputStream</a></span></span>):
   2 <code class="constructorsynopsis">    <span class="methodname"><a class="link" href="class-giobufferedinputstream.html#constructor-giobufferedinputstream" title="Constructor">gio.BufferedInputStream</a></span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>base_stream</code></strong></span></span>)</code><br><code class="methodsynopsis">    def <span class="methodname"><a class="link" href="class-giobufferedinputstream.html#method-giobufferedinputstream--fill" title="gio.BufferedInputStream.fill">fill</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-giobufferedinputstream.html#method-giobufferedinputstream--fill-async" title="gio.BufferedInputStream.fill_async">fill_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-giobufferedinputstream.html#method-giobufferedinputstream--fill-finish" title="gio.BufferedInputStream.fill_finish">fill_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-giobufferedinputstream.html#method-giobufferedinputstream--get-available" title="gio.BufferedInputStream.get_available">get_available</a></span>(<span class="methodparam"></span>)</code><br><code class="methodsynopsis">    def <span class="methodname"><a class="link" href="class-giobufferedinputstream.html#method-giobufferedinputstream--get-buffer-size" title="gio.BufferedInputStream.get_buffer_size">get_buffer_size</a></span>(<span class="methodparam"></span>)</code><br><code class="methodsynopsis">    def <span class="methodname"><a class="link" href="class-giobufferedinputstream.html#method-giobufferedinputstream--read-byte" title="gio.BufferedInputStream.read_byte">read_byte</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-giobufferedinputstream.html#method-giobufferedinputstream--set-buffer-size" title="gio.BufferedInputStream.set_buffer_size">set_buffer_size</a></span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>size</code></strong></span></span>)</code><br></pre></td></tr></table><pre class="programlisting">
   3 <span class="bold"><strong>Functions</strong></span>
   4
   5 <code class="methodsynopsis">    def <span class="methodname"><a class="link" href="class-giobufferedinputstream.html#function-gio--buffered-input-stream-new-sized" title="gio.buffered_input_stream_new_sized">gio.buffered_input_stream_new_sized</a></span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>size</code></strong></span></span>)</code></pre></div><div class="refsect1" title="Ancestry"><a name="id448121"></a><h2>Ancestry</h2><pre class="synopsis">+-- <a class="link" href="class-gobject.html" title="gobject.GObject">gobject.GObject</a>
   6   +-- <a class="link" href="class-gioinputstream.html" title="gio.InputStream">gio.InputStream</a>
   7     +-- <a class="link" href="class-giofilterinputstream.html" title="gio.FilterInputStream">gio.FilterInputStream</a>
   8       +-- <a class="link" href="class-giobufferedinputstream.html" title="gio.BufferedInputStream">gio.BufferedInputStream</a>
   9 </pre></div><div class="refsect1" title="gio.BufferedInputStream Properties"><a name="properties-giobufferedinputstream"></a><h2>gio.BufferedInputStream Properties</h2><div class="blockquote"><table width="100%" border="0" bgcolor="#E0E0E0"><tr><td valign="top"><div class="informaltable"><table width="100%" border="0"><colgroup><col width="1in"><col width="1in"><col width="4in"></colgroup><tbody><tr valign="top"><td valign="top">"buffer-size"</td><td valign="top">Read - Write - Construct</td><td valign="top">The size of the backend buffer. Allowed values: &gt;= 1. Default value: 4096.</td></tr></tbody></table></div></td></tr></table></div></div><div class="refsect1" title="Description"><a name="id500482"></a><h2>Description</h2><p>
  10             <a class="link" href="class-giobufferedinputstream.html" title="gio.BufferedInputStream"><code class="classname">gio.BufferedInputStream</code></a>
  11             implements <a class="link" href="class-giofilterinputstream.html" title="gio.FilterInputStream"><code class="classname">gio.FilterInputStream</code></a>
  12             and provides for buffered reads.
  13         </p><p>
  14             By default,
  15             <a class="link" href="class-giobufferedinputstream.html" title="gio.BufferedInputStream"><code class="classname">gio.BufferedInputStream</code></a>'s
  16             buffer size is set at 4 kilobytes.
  17         </p><p>
  18             To create a buffered input stream, use
  19             <code class="methodname"><a class="link" href="class-giobufferedinputstream.html#constructor-giobufferedinputstream" title="Constructor">gio.BufferedInputStream</a></code>(),
  20             or <code class="methodname"><a class="link" href="class-giobufferedinputstream.html#function-gio--buffered-input-stream-new-sized" title="gio.buffered_input_stream_new_sized">gio.buffered_input_stream_new_sized</a></code>()
  21             to specify the buffer's size at construction.
  22         </p><p>
  23             To get the size of a buffer within a buffered input stream, use
  24             <code class="methodname"><a class="link" href="class-giobufferedinputstream.html#method-giobufferedinputstream--get-buffer-size" title="gio.BufferedInputStream.get_buffer_size">get_buffer_size</a></code>().
  25             To change the size of a buffered input stream's buffer, use
  26             <code class="methodname"><a class="link" href="class-giobufferedinputstream.html#method-giobufferedinputstream--set-buffer-size" title="gio.BufferedInputStream.set_buffer_size">set_buffer_size</a></code>().
  27             Note that the buffer's size cannot be reduced below the size of the data within the buffer.
  28         </p></div><div class="refsect1" title="Constructor"><a name="constructor-giobufferedinputstream"></a><h2>Constructor</h2><pre class="programlisting"><code class="constructorsynopsis">    <span class="methodname">gio.BufferedInputStream</span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>base_stream</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"><em class="parameter"><code>base_stream</code></em> :</span></p></td><td>a
  29                 <a class="link" href="class-gioinputstream.html" title="gio.InputStream"><code class="classname">gio.InputStream</code></a>.
  30                 </td></tr><tr><td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td><td>a new
  31                 <a class="link" href="class-gioinputstream.html" title="gio.InputStream"><code class="classname">gio.InputStream</code></a>
  32                 for the given base_stream.
  33                 </td></tr></tbody></table><p>
  34             Creates a new <a class="link" href="class-gioinputstream.html" title="gio.InputStream"><code class="classname">gio.InputStream</code></a>
  35             from the given base_stream, with a buffer set to the default size (4 kilobytes).
  36         </p></div><div class="refsect1" title="Methods"><a name="id449318"></a><h2>Methods</h2><div class="refsect2" title="gio.BufferedInputStream.fill"><a name="method-giobufferedinputstream--fill"></a><h3>gio.BufferedInputStream.fill</h3><pre class="programlisting"><code class="methodsynopsis">    def <span class="methodname">fill</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 read from the stream.
  37                   </td></tr><tr><td><p><span class="term"><strong class="parameter"><code>cancellable</code></strong> :</span></p></td><td>optional
  38                     <a class="link" href="class-giocancellable.html" title="gio.Cancellable"><code class="classname">gio.Cancellable</code></a>
  39                     object, <code class="literal">None</code> to ignore.
  40                   </td></tr><tr><td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td><td>the number of bytes read into stream's buffer,
  41                     up to count, or -1 on error.
  42                     </td></tr></tbody></table><p>
  43                 The <code class="methodname">fill</code>() method tries to read count bytes
  44                 from the stream into the buffer. Will block during this read.
  45             </p><p>
  46                 If count is zero, returns zero and does nothing. A value of count
  47                 larger than G_MAXSSIZE will cause a gio.ERROR_INVALID_ARGUMENT error.
  48             </p><p>
  49                 On success, the number of bytes read into the buffer is returned. It
  50                 is not an error if this is not the same as the requested size, as it can
  51                 happen e.g. near the end of a file. Zero is returned on end of file
  52                 (or if count is zero), but never otherwise.
  53             </p><p>
  54                 If count is -1 then the attempted read size is equal to the number
  55                 of bytes that are required to fill the buffer.
  56             </p><p>
  57                 If cancellable is not <code class="literal">None</code>, then the operation can
  58                 be cancelled by triggering the cancellable object from another thread.
  59                 If the operation was cancelled, the error gio.ERROR_CANCELLED will be
  60                 returned. If an operation was partially finished when the operation was
  61                 cancelled the partial result will be returned, without an error.
  62             </p><p>
  63                 On error -1 is returned and error is set accordingly.
  64             </p><p>
  65                 For the asynchronous, non-blocking, version of this function, see
  66                 <code class="methodname"><a class="link" href="class-giobufferedinputstream.html#method-giobufferedinputstream--fill-async" title="gio.BufferedInputStream.fill_async">gio.BufferedInputStream.fill_async</a></code>().
  67             </p></div><div class="refsect2" title="gio.BufferedInputStream.fill_async"><a name="method-giobufferedinputstream--fill-async"></a><h3>gio.BufferedInputStream.fill_async</h3><pre class="programlisting"><code class="methodsynopsis">    def <span class="methodname">fill_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"><strong class="parameter"><code>count</code></strong> :</span></p></td><td>the number of bytes that will be read from the stream.
  68                   </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.
  69                     </td></tr><tr><td><p><span class="term"><em class="parameter"><code>io_priority</code></em> :</span></p></td><td>the
  70                     <a class="xref" href="glib-constants.html#glib-priority-constants" title="Glib Priority Constants">Glib Priority Constants</a>
  71                     of the request.
  72                     </td></tr><tr><td><p><span class="term"><em class="parameter"><code>cancellable</code></em> :</span></p></td><td>optional
  73                     <a class="link" href="class-giocancellable.html" title="gio.Cancellable"><code class="classname">gio.Cancellable</code></a>
  74                     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.
  75                     </td></tr></tbody></table><p>
  76                 The <code class="methodname">fill_async</code>() method reads data into stream's
  77                 buffer asynchronously, up to count size. io_priority can be used to
  78                 prioritize reads.
  79             </p><p>
  80                 For the synchronous version of this function, see
  81                 <code class="methodname"><a class="link" href="class-giobufferedinputstream.html#method-giobufferedinputstream--fill" title="gio.BufferedInputStream.fill">gio.BufferedInputStream.fill</a></code>().
  82             </p><p>
  83                 If cancellable is not <code class="literal">None</code>, then the operation can be cancelled
  84                 by triggering the cancellable object from another thread. If the operation was
  85                 cancelled, the error gio.ERROR_CANCELLED will be set
  86             </p><p>
  87                 If count is -1 then the attempted read size is equal to the number of bytes
  88                 that are required to fill the buffer.
  89             </p></div><div class="refsect2" title="gio.BufferedInputStream.fill_finish"><a name="method-giobufferedinputstream--fill-finish"></a><h3>gio.BufferedInputStream.fill_finish</h3><pre class="programlisting"><code class="methodsynopsis">    def <span class="methodname">fill_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>.
  90                   </td></tr><tr><td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td><td>the size of the read stream, or -1 on an error.
  91                     </td></tr></tbody></table><p>
  92                 The <code class="methodname">fill_finish</code>() method finishes an asynchronous
  93                 file append operation started with
  94                 <code class="methodname"><a class="link" href="class-giobufferedinputstream.html#method-giobufferedinputstream--fill-async" title="gio.BufferedInputStream.fill_async">gio.BufferedInputStream.fill_async</a></code>().
  95             </p></div><div class="refsect2" title="gio.BufferedInputStream.get_available"><a name="method-giobufferedinputstream--get-available"></a><h3>gio.BufferedInputStream.get_available</h3><pre class="programlisting"><code class="methodsynopsis">    def <span class="methodname">get_available</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>size of the available stream.
  96                     </td></tr></tbody></table><p>
  97                 The <code class="methodname">get_available</code>() method gets the size of
  98                 the available data within the stream.
  99             </p></div><div class="refsect2" title="gio.BufferedInputStream.get_buffer_size"><a name="method-giobufferedinputstream--get-buffer-size"></a><h3>gio.BufferedInputStream.get_buffer_size</h3><pre class="programlisting"><code class="methodsynopsis">    def <span class="methodname">get_buffer_size</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>the current buffer size.
 100                     </td></tr></tbody></table><p>
 101                 The <code class="methodname">get_buffer_size</code>() method gets the size
 102                 of the input buffer.
 103             </p></div><div class="refsect2" title="gio.BufferedInputStream.read_byte"><a name="method-giobufferedinputstream--read-byte"></a><h3>gio.BufferedInputStream.read_byte</h3><pre class="programlisting"><code class="methodsynopsis">    def <span class="methodname">read_byte</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
 104                     <a class="link" href="class-giocancellable.html" title="gio.Cancellable"><code class="classname">gio.Cancellable</code></a>
 105                     object, <code class="literal">None</code> to ignore.
 106                   </td></tr><tr><td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td><td>the byte read from the stream, or -1 on end of stream or error.
 107                     </td></tr></tbody></table><p>
 108                 The <code class="methodname">read_byte</code>() method tries to read a single
 109                 byte from the stream or the buffer. Will block during this read.
 110             </p><p>
 111                 On success, the byte read from the stream is returned. On end of stream -1
 112                 is returned but it's not an exceptional error and error is not set.
 113             </p><p>
 114                 If cancellable is not <code class="literal">None</code>, then the operation can
 115                 be cancelled by triggering the cancellable object from another thread.
 116                 If the operation was cancelled, the error gio.ERROR_CANCELLED will be
 117                 returned. If an operation was partially finished when the operation was
 118                 cancelled the partial result will be returned, without an error.
 119             </p><p>
 120                 On error -1 is returned and error is set accordingly.
 121             </p></div><div class="refsect2" title="gio.BufferedInputStream.set_buffer_size"><a name="method-giobufferedinputstream--set-buffer-size"></a><h3>gio.BufferedInputStream.set_buffer_size</h3><pre class="programlisting"><code class="methodsynopsis">    def <span class="methodname">set_buffer_size</span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>size</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>size</code></strong> :</span></p></td><td>the new buffer size.
 122                   </td></tr></tbody></table><p>
 123                 The <code class="methodname">set_buffer_size</code>() method sets the size
 124                 of the internal buffer of stream to size, or to the size of the contents
 125                 of the buffer. The buffer can never be resized smaller than its current contents.
 126             </p></div></div><div class="refsect1" title="Functions"><a name="id353937"></a><h2>Functions</h2><div class="refsect2" title="gio.buffered_input_stream_new_sized"><a name="function-gio--buffered-input-stream-new-sized"></a><h3>gio.buffered_input_stream_new_sized</h3><pre class="programlisting"><code class="methodsynopsis">    def <span class="methodname">buffered_input_stream_new_sized</span>(<span class="methodparam"><span class="parameter"><strong class="parameter"><code>size</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"><em class="parameter"><code>size</code></em> :</span></p></td><td>the requested buffer size.
 127                     </td></tr><tr><td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td><td>A new
 128                     <a class="link" href="class-gioinputstream.html" title="gio.InputStream"><code class="classname">gio.InputStream</code></a>.
 129                     </td></tr></tbody></table><p>
 130                 The <code class="methodname">buffered_input_stream_new_sized</code>() function creates
 131                 a new <a class="link" href="class-giobufferedinputstream.html" title="gio.BufferedInputStream"><code class="classname">gio.BufferedInputStream</code></a>
 132                 from the given base_stream, with a buffer set to size.
 133             </p></div></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="class-gioasyncresult.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="gio-class-reference.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="class-giobufferedoutputstream.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">gio.AsyncResult </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> gio.BufferedOutputStream</td></tr></table></div></body></html>