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| <a href="#gstreamer-GstIterator.synopsis" class="shortcut">Top</a> |
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| <a href="#gstreamer-GstIterator.description" class="shortcut">Description</a> |
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| <a name="gstreamer-GstIterator"></a><div class="titlepage"></div> |
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| <h2><span class="refentrytitle"><a name="gstreamer-GstIterator.top_of_page"></a>GstIterator</span></h2> |
| <p>GstIterator — Object to retrieve multiple elements in a threadsafe |
| way.</p> |
| </td> |
| <td valign="top" align="right"></td> |
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| <div class="refsynopsisdiv"> |
| <a name="gstreamer-GstIterator.synopsis"></a><h2>Synopsis</h2> |
| <pre class="synopsis"> |
| #include <gst/gst.h> |
| |
| struct <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator">GstIterator</a>; |
| enum <a class="link" href="gstreamer-GstIterator.html#GstIteratorItem" title="enum GstIteratorItem">GstIteratorItem</a>; |
| enum <a class="link" href="gstreamer-GstIterator.html#GstIteratorResult" title="enum GstIteratorResult">GstIteratorResult</a>; |
| <span class="returnvalue">void</span> (<a class="link" href="gstreamer-GstIterator.html#GstIteratorCopyFunction" title="GstIteratorCopyFunction ()">*GstIteratorCopyFunction</a>) (<em class="parameter"><code>const <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *copy</code></em>); |
| <a class="link" href="gstreamer-GstIterator.html#GstIteratorResult" title="enum GstIteratorResult"><span class="returnvalue">GstIteratorResult</span></a> (<a class="link" href="gstreamer-GstIterator.html#GstIteratorNextFunction" title="GstIteratorNextFunction ()">*GstIteratorNextFunction</a>) (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> *result</code></em>); |
| <a class="link" href="gstreamer-GstIterator.html#GstIteratorItem" title="enum GstIteratorItem"><span class="returnvalue">GstIteratorItem</span></a> (<a class="link" href="gstreamer-GstIterator.html#GstIteratorItemFunction" title="GstIteratorItemFunction ()">*GstIteratorItemFunction</a>) (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>, |
| <em class="parameter"><code>const <a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> *item</code></em>); |
| <span class="returnvalue">void</span> (<a class="link" href="gstreamer-GstIterator.html#GstIteratorResyncFunction" title="GstIteratorResyncFunction ()">*GstIteratorResyncFunction</a>) (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>); |
| <span class="returnvalue">void</span> (<a class="link" href="gstreamer-GstIterator.html#GstIteratorFreeFunction" title="GstIteratorFreeFunction ()">*GstIteratorFreeFunction</a>) (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>); |
| <span class="returnvalue">void</span> (<a class="link" href="gstreamer-GstIterator.html#GstIteratorForeachFunction" title="GstIteratorForeachFunction ()">*GstIteratorForeachFunction</a>) (<em class="parameter"><code>const <a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> *item</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gpointer"><span class="type">gpointer</span></a> user_data</code></em>); |
| <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a> (<a class="link" href="gstreamer-GstIterator.html#GstIteratorFoldFunction" title="GstIteratorFoldFunction ()">*GstIteratorFoldFunction</a>) (<em class="parameter"><code>const <a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> *item</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> *ret</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gpointer"><span class="type">gpointer</span></a> user_data</code></em>); |
| #define <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR:CAPS" title="GST_ITERATOR()">GST_ITERATOR</a> (it) |
| #define <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-LOCK:CAPS" title="GST_ITERATOR_LOCK()">GST_ITERATOR_LOCK</a> (it) |
| #define <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-COOKIE:CAPS" title="GST_ITERATOR_COOKIE()">GST_ITERATOR_COOKIE</a> (it) |
| #define <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-ORIG-COOKIE:CAPS" title="GST_ITERATOR_ORIG_COOKIE()">GST_ITERATOR_ORIG_COOKIE</a> (it) |
| <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> * <a class="link" href="gstreamer-GstIterator.html#gst-iterator-new" title="gst_iterator_new ()">gst_iterator_new</a> (<em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#guint"><span class="type">guint</span></a> size</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/gobject/unstable/gobject-Type-Information.html#GType"><span class="type">GType</span></a> type</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Threads.html#GMutex"><span class="type">GMutex</span></a> *lock</code></em>, |
| <em class="parameter"><code><span class="type">guint32</span> *master_cookie</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorCopyFunction" title="GstIteratorCopyFunction ()"><span class="type">GstIteratorCopyFunction</span></a> copy</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorNextFunction" title="GstIteratorNextFunction ()"><span class="type">GstIteratorNextFunction</span></a> next</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorItemFunction" title="GstIteratorItemFunction ()"><span class="type">GstIteratorItemFunction</span></a> item</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorResyncFunction" title="GstIteratorResyncFunction ()"><span class="type">GstIteratorResyncFunction</span></a> resync</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorFreeFunction" title="GstIteratorFreeFunction ()"><span class="type">GstIteratorFreeFunction</span></a> free</code></em>); |
| <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> * <a class="link" href="gstreamer-GstIterator.html#gst-iterator-new-list" title="gst_iterator_new_list ()">gst_iterator_new_list</a> (<em class="parameter"><code><a href="http://library.gnome.org/devel/gobject/unstable/gobject-Type-Information.html#GType"><span class="type">GType</span></a> type</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Threads.html#GMutex"><span class="type">GMutex</span></a> *lock</code></em>, |
| <em class="parameter"><code><span class="type">guint32</span> *master_cookie</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Doubly-Linked-Lists.html#GList"><span class="type">GList</span></a> **list</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/gobject/unstable/gobject-The-Base-Object-Type.html#GObject"><span class="type">GObject</span></a> *owner</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorItemFunction" title="GstIteratorItemFunction ()"><span class="type">GstIteratorItemFunction</span></a> item</code></em>); |
| <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> * <a class="link" href="gstreamer-GstIterator.html#gst-iterator-new-single" title="gst_iterator_new_single ()">gst_iterator_new_single</a> (<em class="parameter"><code><a href="http://library.gnome.org/devel/gobject/unstable/gobject-Type-Information.html#GType"><span class="type">GType</span></a> type</code></em>, |
| <em class="parameter"><code>const <a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> *object</code></em>); |
| <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> * <a class="link" href="gstreamer-GstIterator.html#gst-iterator-copy" title="gst_iterator_copy ()">gst_iterator_copy</a> (<em class="parameter"><code>const <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>); |
| <span class="returnvalue">void</span> <a class="link" href="gstreamer-GstIterator.html#gst-iterator-free" title="gst_iterator_free ()">gst_iterator_free</a> (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>); |
| <a class="link" href="gstreamer-GstIterator.html#GstIteratorResult" title="enum GstIteratorResult"><span class="returnvalue">GstIteratorResult</span></a> <a class="link" href="gstreamer-GstIterator.html#gst-iterator-next" title="gst_iterator_next ()">gst_iterator_next</a> (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> *elem</code></em>); |
| <span class="returnvalue">void</span> <a class="link" href="gstreamer-GstIterator.html#gst-iterator-resync" title="gst_iterator_resync ()">gst_iterator_resync</a> (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>); |
| <span class="returnvalue">void</span> <a class="link" href="gstreamer-GstIterator.html#gst-iterator-push" title="gst_iterator_push ()">gst_iterator_push</a> (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *other</code></em>); |
| <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> * <a class="link" href="gstreamer-GstIterator.html#gst-iterator-filter" title="gst_iterator_filter ()">gst_iterator_filter</a> (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Doubly-Linked-Lists.html#GCompareFunc"><span class="type">GCompareFunc</span></a> func</code></em>, |
| <em class="parameter"><code>const <a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> *user_data</code></em>); |
| <a class="link" href="gstreamer-GstIterator.html#GstIteratorResult" title="enum GstIteratorResult"><span class="returnvalue">GstIteratorResult</span></a> <a class="link" href="gstreamer-GstIterator.html#gst-iterator-fold" title="gst_iterator_fold ()">gst_iterator_fold</a> (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorFoldFunction" title="GstIteratorFoldFunction ()"><span class="type">GstIteratorFoldFunction</span></a> func</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> *ret</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gpointer"><span class="type">gpointer</span></a> user_data</code></em>); |
| <a class="link" href="gstreamer-GstIterator.html#GstIteratorResult" title="enum GstIteratorResult"><span class="returnvalue">GstIteratorResult</span></a> <a class="link" href="gstreamer-GstIterator.html#gst-iterator-foreach" title="gst_iterator_foreach ()">gst_iterator_foreach</a> (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorForeachFunction" title="GstIteratorForeachFunction ()"><span class="type">GstIteratorForeachFunction</span></a> func</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gpointer"><span class="type">gpointer</span></a> user_data</code></em>); |
| <a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a> <a class="link" href="gstreamer-GstIterator.html#gst-iterator-find-custom" title="gst_iterator_find_custom ()">gst_iterator_find_custom</a> (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Doubly-Linked-Lists.html#GCompareFunc"><span class="type">GCompareFunc</span></a> func</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> *elem</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gpointer"><span class="type">gpointer</span></a> user_data</code></em>); |
| </pre> |
| </div> |
| <div class="refsect1"> |
| <a name="gstreamer-GstIterator.description"></a><h2>Description</h2> |
| <p> |
| A GstIterator is used to retrieve multiple objects from another object in |
| a threadsafe way. |
| </p> |
| <p> |
| Various GStreamer objects provide access to their internal structures using |
| an iterator. |
| </p> |
| <p> |
| In general, whenever calling a GstIterator function results in your code |
| receiving a refcounted object, the refcount for that object will have been |
| increased. Your code is responsible for unrefing that object after use. |
| </p> |
| <p> |
| The basic use pattern of an iterator is as follows: |
| </p> |
| <p> |
| </p> |
| <div class="example"> |
| <a name="idp21236752"></a><p class="title"><b>Example 9. Using an iterator</b></p> |
| <div class="example-contents"> |
| <table class="listing_frame" border="0" cellpadding="0" cellspacing="0"> |
| <tbody> |
| <tr> |
| <td class="listing_lines" align="right"><pre>1 |
| 2 |
| 3 |
| 4 |
| 5 |
| 6 |
| 7 |
| 8 |
| 9 |
| 10 |
| 11 |
| 12 |
| 13 |
| 14 |
| 15 |
| 16 |
| 17 |
| 18 |
| 19 |
| 20 |
| 21 |
| 22 |
| 23</pre></td> |
| <td class="listing_code"><pre class="programlisting">it <span class="gtkdoc opt">=</span> <span class="function">_get_iterator</span><span class="gtkdoc opt">(</span>object<span class="gtkdoc opt">);</span> |
| done <span class="gtkdoc opt">=</span> FALSE<span class="gtkdoc opt">;</span> |
| <span class="keyword">while</span> <span class="gtkdoc opt">(!</span>done<span class="gtkdoc opt">) {</span> |
| <span class="keyword">switch</span> <span class="gtkdoc opt">(</span><span class="function"><a href="../gstreamer-1.0/gstreamer-GstIterator.html#gst-iterator-next">gst_iterator_next</a></span> <span class="gtkdoc opt">(</span>it<span class="gtkdoc opt">, &</span>item<span class="gtkdoc opt">)) {</span> |
| <span class="keyword">case</span> GST_ITERATOR_OK<span class="gtkdoc opt">:</span> |
| <span class="gtkdoc opt">...</span> use<span class="gtkdoc opt">/</span>change item here<span class="gtkdoc opt">...</span> |
| <span class="function"><a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#g-value-reset">g_value_reset</a></span> <span class="gtkdoc opt">(&</span>item<span class="gtkdoc opt">);</span> |
| <span class="keyword">break</span><span class="gtkdoc opt">;</span> |
| <span class="keyword">case</span> GST_ITERATOR_RESYNC<span class="gtkdoc opt">:</span> |
| <span class="gtkdoc opt">...</span>rollback changes to items<span class="gtkdoc opt">...</span> |
| <span class="function"><a href="../gstreamer-1.0/gstreamer-GstIterator.html#gst-iterator-resync">gst_iterator_resync</a></span> <span class="gtkdoc opt">(</span>it<span class="gtkdoc opt">);</span> |
| <span class="keyword">break</span><span class="gtkdoc opt">;</span> |
| <span class="keyword">case</span> GST_ITERATOR_ERROR<span class="gtkdoc opt">:</span> |
| <span class="gtkdoc opt">...</span>wrong parameters were given<span class="gtkdoc opt">...</span> |
| done <span class="gtkdoc opt">=</span> TRUE<span class="gtkdoc opt">;</span> |
| <span class="keyword">break</span><span class="gtkdoc opt">;</span> |
| <span class="keyword">case</span> GST_ITERATOR_DONE<span class="gtkdoc opt">:</span> |
| done <span class="gtkdoc opt">=</span> TRUE<span class="gtkdoc opt">;</span> |
| <span class="keyword">break</span><span class="gtkdoc opt">;</span> |
| <span class="gtkdoc opt">}</span> |
| <span class="gtkdoc opt">}</span> |
| <span class="function"><a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#g-value-unset">g_value_unset</a></span> <span class="gtkdoc opt">(&</span>item<span class="gtkdoc opt">);</span> |
| <span class="function"><a href="../gstreamer-1.0/gstreamer-GstIterator.html#gst-iterator-free">gst_iterator_free</a></span> <span class="gtkdoc opt">(</span>it<span class="gtkdoc opt">);</span></pre></td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| |
| </div> |
| <p><br class="example-break"> |
| </p> |
| <p> |
| Last reviewed on 2009-06-16 (0.10.24) |
| </p> |
| </div> |
| <div class="refsect1"> |
| <a name="gstreamer-GstIterator.details"></a><h2>Details</h2> |
| <div class="refsect2"> |
| <a name="GstIterator"></a><h3>struct GstIterator</h3> |
| <pre class="programlisting">struct GstIterator { |
| }; |
| </pre> |
| <p> |
| <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> base structure. The values of this structure are |
| protected for subclasses, use the methods to use the <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a>. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody></tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GstIteratorItem"></a><h3>enum GstIteratorItem</h3> |
| <pre class="programlisting">typedef enum { |
| GST_ITERATOR_ITEM_SKIP = 0, |
| GST_ITERATOR_ITEM_PASS = 1, |
| GST_ITERATOR_ITEM_END = 2 |
| } GstIteratorItem; |
| </pre> |
| <p> |
| The result of a <a class="link" href="gstreamer-GstIterator.html#GstIteratorItemFunction" title="GstIteratorItemFunction ()"><span class="type">GstIteratorItemFunction</span></a>. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><a name="GST-ITERATOR-ITEM-SKIP:CAPS"></a><span class="term"><code class="literal">GST_ITERATOR_ITEM_SKIP</code></span></p></td> |
| <td>Skip this item |
| </td> |
| </tr> |
| <tr> |
| <td><p><a name="GST-ITERATOR-ITEM-PASS:CAPS"></a><span class="term"><code class="literal">GST_ITERATOR_ITEM_PASS</code></span></p></td> |
| <td>Return item |
| </td> |
| </tr> |
| <tr> |
| <td><p><a name="GST-ITERATOR-ITEM-END:CAPS"></a><span class="term"><code class="literal">GST_ITERATOR_ITEM_END</code></span></p></td> |
| <td>Stop after this item. |
| </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GstIteratorResult"></a><h3>enum GstIteratorResult</h3> |
| <pre class="programlisting">typedef enum { |
| GST_ITERATOR_DONE = 0, |
| GST_ITERATOR_OK = 1, |
| GST_ITERATOR_RESYNC = 2, |
| GST_ITERATOR_ERROR = 3 |
| } GstIteratorResult; |
| </pre> |
| <p> |
| The result of <a class="link" href="gstreamer-GstIterator.html#gst-iterator-next" title="gst_iterator_next ()"><code class="function">gst_iterator_next()</code></a>. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><a name="GST-ITERATOR-DONE:CAPS"></a><span class="term"><code class="literal">GST_ITERATOR_DONE</code></span></p></td> |
| <td>No more items in the iterator |
| </td> |
| </tr> |
| <tr> |
| <td><p><a name="GST-ITERATOR-OK:CAPS"></a><span class="term"><code class="literal">GST_ITERATOR_OK</code></span></p></td> |
| <td>An item was retrieved |
| </td> |
| </tr> |
| <tr> |
| <td><p><a name="GST-ITERATOR-RESYNC:CAPS"></a><span class="term"><code class="literal">GST_ITERATOR_RESYNC</code></span></p></td> |
| <td>Datastructure changed while iterating |
| </td> |
| </tr> |
| <tr> |
| <td><p><a name="GST-ITERATOR-ERROR:CAPS"></a><span class="term"><code class="literal">GST_ITERATOR_ERROR</code></span></p></td> |
| <td>An error happened |
| </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GstIteratorCopyFunction"></a><h3>GstIteratorCopyFunction ()</h3> |
| <pre class="programlisting"><span class="returnvalue">void</span> (*GstIteratorCopyFunction) (<em class="parameter"><code>const <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *copy</code></em>);</pre> |
| <p> |
| This function will be called when creating a copy of <em class="parameter"><code>it</code></em> and should |
| create a copy of all custom iterator fields or increase their |
| reference counts. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>it</code></em> :</span></p></td> |
| <td>The original iterator</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>copy</code></em> :</span></p></td> |
| <td>The copied iterator</td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GstIteratorNextFunction"></a><h3>GstIteratorNextFunction ()</h3> |
| <pre class="programlisting"><a class="link" href="gstreamer-GstIterator.html#GstIteratorResult" title="enum GstIteratorResult"><span class="returnvalue">GstIteratorResult</span></a> (*GstIteratorNextFunction) (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> *result</code></em>);</pre> |
| <p> |
| The function that will be called when the next element of the iterator |
| should be retrieved. |
| </p> |
| <p> |
| Implementors of a <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> should implement this |
| function and pass it to the constructor of the custom iterator. |
| The function will be called with the iterator lock held. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>it</code></em> :</span></p></td> |
| <td>the iterator</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>result</code></em> :</span></p></td> |
| <td>a pointer to hold the next item</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td>the result of the operation.</td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GstIteratorItemFunction"></a><h3>GstIteratorItemFunction ()</h3> |
| <pre class="programlisting"><a class="link" href="gstreamer-GstIterator.html#GstIteratorItem" title="enum GstIteratorItem"><span class="returnvalue">GstIteratorItem</span></a> (*GstIteratorItemFunction) (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>, |
| <em class="parameter"><code>const <a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> *item</code></em>);</pre> |
| <p> |
| The function that will be called after the next item of the iterator |
| has been retrieved. This function can be used to skip items or stop |
| the iterator. |
| </p> |
| <p> |
| The function will be called with the iterator lock held. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>it</code></em> :</span></p></td> |
| <td>the iterator</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td> |
| <td>the item being retrieved.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td>the result of the operation.</td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GstIteratorResyncFunction"></a><h3>GstIteratorResyncFunction ()</h3> |
| <pre class="programlisting"><span class="returnvalue">void</span> (*GstIteratorResyncFunction) (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>);</pre> |
| <p> |
| This function will be called whenever a concurrent update happened |
| to the iterated datastructure. The implementor of the iterator should |
| restart the iterator from the beginning and clean up any state it might |
| have. |
| </p> |
| <p> |
| Implementors of a <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> should implement this |
| function and pass it to the constructor of the custom iterator. |
| The function will be called with the iterator lock held. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody><tr> |
| <td><p><span class="term"><em class="parameter"><code>it</code></em> :</span></p></td> |
| <td>the iterator</td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GstIteratorFreeFunction"></a><h3>GstIteratorFreeFunction ()</h3> |
| <pre class="programlisting"><span class="returnvalue">void</span> (*GstIteratorFreeFunction) (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>);</pre> |
| <p> |
| This function will be called when the iterator is freed. |
| </p> |
| <p> |
| Implementors of a <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> should implement this |
| function and pass it to the constructor of the custom iterator. |
| The function will be called with the iterator lock held. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody><tr> |
| <td><p><span class="term"><em class="parameter"><code>it</code></em> :</span></p></td> |
| <td>the iterator</td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GstIteratorForeachFunction"></a><h3>GstIteratorForeachFunction ()</h3> |
| <pre class="programlisting"><span class="returnvalue">void</span> (*GstIteratorForeachFunction) (<em class="parameter"><code>const <a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> *item</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gpointer"><span class="type">gpointer</span></a> user_data</code></em>);</pre> |
| <p> |
| A function that is called by <a class="link" href="gstreamer-GstIterator.html#gst-iterator-foreach" title="gst_iterator_foreach ()"><code class="function">gst_iterator_foreach()</code></a> for every element. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td> |
| <td>The item</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>user_data</code></em> :</span></p></td> |
| <td>User data</td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GstIteratorFoldFunction"></a><h3>GstIteratorFoldFunction ()</h3> |
| <pre class="programlisting"><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a> (*GstIteratorFoldFunction) (<em class="parameter"><code>const <a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> *item</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> *ret</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gpointer"><span class="type">gpointer</span></a> user_data</code></em>);</pre> |
| <p> |
| A function to be passed to <a class="link" href="gstreamer-GstIterator.html#gst-iterator-fold" title="gst_iterator_fold ()"><code class="function">gst_iterator_fold()</code></a>. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td> |
| <td>the item to fold</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>ret</code></em> :</span></p></td> |
| <td>a <a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> collecting the result</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>user_data</code></em> :</span></p></td> |
| <td>data passed to <a class="link" href="gstreamer-GstIterator.html#gst-iterator-fold" title="gst_iterator_fold ()"><code class="function">gst_iterator_fold()</code></a> |
| </td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td>TRUE if the fold should continue, FALSE if it should stop.</td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GST-ITERATOR:CAPS"></a><h3>GST_ITERATOR()</h3> |
| <pre class="programlisting">#define GST_ITERATOR(it) ((GstIterator*)(it)) |
| </pre> |
| <p> |
| Macro to cast to a <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody><tr> |
| <td><p><span class="term"><em class="parameter"><code>it</code></em> :</span></p></td> |
| <td>the <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> value</td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GST-ITERATOR-LOCK:CAPS"></a><h3>GST_ITERATOR_LOCK()</h3> |
| <pre class="programlisting">#define GST_ITERATOR_LOCK(it) (GST_ITERATOR(it)->lock) |
| </pre> |
| <p> |
| Macro to get the lock protecting the datastructure being iterated. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody><tr> |
| <td><p><span class="term"><em class="parameter"><code>it</code></em> :</span></p></td> |
| <td>the <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to get the lock of</td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GST-ITERATOR-COOKIE:CAPS"></a><h3>GST_ITERATOR_COOKIE()</h3> |
| <pre class="programlisting">#define GST_ITERATOR_COOKIE(it) (GST_ITERATOR(it)->cookie) |
| </pre> |
| <p> |
| Macro to get the cookie of a <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a>. The cookie of the |
| iterator is the value of the master cookie when the iterator |
| was created. |
| Whenever the iterator is iterated, the value is compared to the |
| value of the master cookie. If they are different, a concurrent |
| modification happened to the iterator and a resync is needed. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody><tr> |
| <td><p><span class="term"><em class="parameter"><code>it</code></em> :</span></p></td> |
| <td>the <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to get the cookie of</td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="GST-ITERATOR-ORIG-COOKIE:CAPS"></a><h3>GST_ITERATOR_ORIG_COOKIE()</h3> |
| <pre class="programlisting">#define GST_ITERATOR_ORIG_COOKIE(it) (GST_ITERATOR(it)->master_cookie) |
| </pre> |
| <p> |
| Macro to get a pointer to where the master cookie is stored. The |
| master cookie protects the structure being iterated and gets updated |
| whenever the datastructure changes. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody><tr> |
| <td><p><span class="term"><em class="parameter"><code>it</code></em> :</span></p></td> |
| <td>the <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to get the master cookie of</td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-iterator-new"></a><h3>gst_iterator_new ()</h3> |
| <pre class="programlisting"><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> * gst_iterator_new (<em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#guint"><span class="type">guint</span></a> size</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/gobject/unstable/gobject-Type-Information.html#GType"><span class="type">GType</span></a> type</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Threads.html#GMutex"><span class="type">GMutex</span></a> *lock</code></em>, |
| <em class="parameter"><code><span class="type">guint32</span> *master_cookie</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorCopyFunction" title="GstIteratorCopyFunction ()"><span class="type">GstIteratorCopyFunction</span></a> copy</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorNextFunction" title="GstIteratorNextFunction ()"><span class="type">GstIteratorNextFunction</span></a> next</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorItemFunction" title="GstIteratorItemFunction ()"><span class="type">GstIteratorItemFunction</span></a> item</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorResyncFunction" title="GstIteratorResyncFunction ()"><span class="type">GstIteratorResyncFunction</span></a> resync</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorFreeFunction" title="GstIteratorFreeFunction ()"><span class="type">GstIteratorFreeFunction</span></a> free</code></em>);</pre> |
| <p> |
| Create a new iterator. This function is mainly used for objects |
| implementing the next/resync/free function to iterate a data structure. |
| </p> |
| <p> |
| For each item retrieved, the <em class="parameter"><code>item</code></em> function is called with the lock |
| held. The <em class="parameter"><code>free</code></em> function is called when the iterator is freed. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>size</code></em> :</span></p></td> |
| <td>the size of the iterator structure</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>type</code></em> :</span></p></td> |
| <td> |
| <a href="http://library.gnome.org/devel/gobject/unstable/gobject-Type-Information.html#GType"><span class="type">GType</span></a> of children</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>lock</code></em> :</span></p></td> |
| <td>pointer to a <a href="http://library.gnome.org/devel/glib/unstable/glib-Threads.html#GMutex"><span class="type">GMutex</span></a>.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>master_cookie</code></em> :</span></p></td> |
| <td>pointer to a guint32 that is changed when the items in the |
| iterator changed.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>copy</code></em> :</span></p></td> |
| <td>copy function</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>next</code></em> :</span></p></td> |
| <td>function to get next item</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td> |
| <td>function to call on each item retrieved</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>resync</code></em> :</span></p></td> |
| <td>function to resync the iterator</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>free</code></em> :</span></p></td> |
| <td>function to free the iterator</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td>the new <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a>. |
| MT safe.</td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-iterator-new-list"></a><h3>gst_iterator_new_list ()</h3> |
| <pre class="programlisting"><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> * gst_iterator_new_list (<em class="parameter"><code><a href="http://library.gnome.org/devel/gobject/unstable/gobject-Type-Information.html#GType"><span class="type">GType</span></a> type</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Threads.html#GMutex"><span class="type">GMutex</span></a> *lock</code></em>, |
| <em class="parameter"><code><span class="type">guint32</span> *master_cookie</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Doubly-Linked-Lists.html#GList"><span class="type">GList</span></a> **list</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/gobject/unstable/gobject-The-Base-Object-Type.html#GObject"><span class="type">GObject</span></a> *owner</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorItemFunction" title="GstIteratorItemFunction ()"><span class="type">GstIteratorItemFunction</span></a> item</code></em>);</pre> |
| <p> |
| Create a new iterator designed for iterating <em class="parameter"><code>list</code></em>. |
| </p> |
| <p> |
| The list you iterate is usually part of a data structure <em class="parameter"><code>owner</code></em> and is |
| protected with <em class="parameter"><code>lock</code></em>. |
| </p> |
| <p> |
| The iterator will use <em class="parameter"><code>lock</code></em> to retrieve the next item of the list and it |
| will then call the <em class="parameter"><code>item</code></em> function before releasing <em class="parameter"><code>lock</code></em> again. |
| </p> |
| <p> |
| When a concurrent update to the list is performed, usually by <em class="parameter"><code>owner</code></em> while |
| holding <em class="parameter"><code>lock</code></em>, <em class="parameter"><code>master_cookie</code></em> will be updated. The iterator implementation |
| will notice the update of the cookie and will return <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-RESYNC:CAPS"><code class="literal">GST_ITERATOR_RESYNC</code></a> to |
| the user of the iterator in the next call to <a class="link" href="gstreamer-GstIterator.html#gst-iterator-next" title="gst_iterator_next ()"><code class="function">gst_iterator_next()</code></a>. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>type</code></em> :</span></p></td> |
| <td> |
| <a href="http://library.gnome.org/devel/gobject/unstable/gobject-Type-Information.html#GType"><span class="type">GType</span></a> of elements</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>lock</code></em> :</span></p></td> |
| <td>pointer to a <a href="http://library.gnome.org/devel/glib/unstable/glib-Threads.html#GMutex"><span class="type">GMutex</span></a> protecting the list.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>master_cookie</code></em> :</span></p></td> |
| <td>pointer to a guint32 that is incremented when the list |
| is changed.</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>list</code></em> :</span></p></td> |
| <td>pointer to the list</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>owner</code></em> :</span></p></td> |
| <td>object owning the list</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>item</code></em> :</span></p></td> |
| <td>function to call on each item retrieved</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td>the new <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> for <em class="parameter"><code>list</code></em>. |
| MT safe.</td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-iterator-new-single"></a><h3>gst_iterator_new_single ()</h3> |
| <pre class="programlisting"><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> * gst_iterator_new_single (<em class="parameter"><code><a href="http://library.gnome.org/devel/gobject/unstable/gobject-Type-Information.html#GType"><span class="type">GType</span></a> type</code></em>, |
| <em class="parameter"><code>const <a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> *object</code></em>);</pre> |
| <p> |
| This <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> is a convenient iterator for the common |
| case where a <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> needs to be returned but only |
| a single object has to be considered. This happens often |
| for the <a class="link" href="GstPad.html#GstPadIterIntLinkFunction" title="GstPadIterIntLinkFunction ()"><span class="type">GstPadIterIntLinkFunction</span></a>. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>type</code></em> :</span></p></td> |
| <td> |
| <a href="http://library.gnome.org/devel/gobject/unstable/gobject-Type-Information.html#GType"><span class="type">GType</span></a> of the passed object</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>object</code></em> :</span></p></td> |
| <td>object that this iterator should return</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td>the new <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> for <em class="parameter"><code>object</code></em>.</td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-iterator-copy"></a><h3>gst_iterator_copy ()</h3> |
| <pre class="programlisting"><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> * gst_iterator_copy (<em class="parameter"><code>const <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>);</pre> |
| <p> |
| Copy the iterator and its state. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>it</code></em> :</span></p></td> |
| <td>a <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> |
| </td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td>a new copy of <em class="parameter"><code>it</code></em>.</td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-iterator-free"></a><h3>gst_iterator_free ()</h3> |
| <pre class="programlisting"><span class="returnvalue">void</span> gst_iterator_free (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>);</pre> |
| <p> |
| Free the iterator. |
| </p> |
| <p> |
| MT safe. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody><tr> |
| <td><p><span class="term"><em class="parameter"><code>it</code></em> :</span></p></td> |
| <td>The <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to free</td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-iterator-next"></a><h3>gst_iterator_next ()</h3> |
| <pre class="programlisting"><a class="link" href="gstreamer-GstIterator.html#GstIteratorResult" title="enum GstIteratorResult"><span class="returnvalue">GstIteratorResult</span></a> gst_iterator_next (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> *elem</code></em>);</pre> |
| <p> |
| Get the next item from the iterator in <em class="parameter"><code>elem</code></em>. |
| </p> |
| <p> |
| Only when this function returns <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-OK:CAPS"><code class="literal">GST_ITERATOR_OK</code></a>, <em class="parameter"><code>elem</code></em> will contain a valid |
| value. <em class="parameter"><code>elem</code></em> must have been initialized to the type of the iterator or |
| initialized to zeroes with <a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#g-value-unset"><code class="function">g_value_unset()</code></a>. The caller is responsible for |
| unsetting or resetting <em class="parameter"><code>elem</code></em> with <a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#g-value-unset"><code class="function">g_value_unset()</code></a> or <a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#g-value-reset"><code class="function">g_value_reset()</code></a> |
| after usage. |
| </p> |
| <p> |
| When this function returns <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-DONE:CAPS"><code class="literal">GST_ITERATOR_DONE</code></a>, no more elements can be |
| retrieved from <em class="parameter"><code>it</code></em>. |
| </p> |
| <p> |
| A return value of <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-RESYNC:CAPS"><code class="literal">GST_ITERATOR_RESYNC</code></a> indicates that the element list was |
| concurrently updated. The user of <em class="parameter"><code>it</code></em> should call <a class="link" href="gstreamer-GstIterator.html#gst-iterator-resync" title="gst_iterator_resync ()"><code class="function">gst_iterator_resync()</code></a> to |
| get the newly updated list. |
| </p> |
| <p> |
| A return value of <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-ERROR:CAPS"><code class="literal">GST_ITERATOR_ERROR</code></a> indicates an unrecoverable fatal error. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>it</code></em> :</span></p></td> |
| <td>The <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to iterate</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>elem</code></em> :</span></p></td> |
| <td>pointer to hold next element. <span class="annotation">[<acronym title="Parameter for returning results. Default is transfer full."><span class="acronym">out</span></acronym> caller-allocates]</span> |
| </td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td>The result of the iteration. Unset <em class="parameter"><code>elem</code></em> after usage. |
| MT safe.</td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-iterator-resync"></a><h3>gst_iterator_resync ()</h3> |
| <pre class="programlisting"><span class="returnvalue">void</span> gst_iterator_resync (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>);</pre> |
| <p> |
| Resync the iterator. this function is mostly called |
| after <a class="link" href="gstreamer-GstIterator.html#gst-iterator-next" title="gst_iterator_next ()"><code class="function">gst_iterator_next()</code></a> returned <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-RESYNC:CAPS"><code class="literal">GST_ITERATOR_RESYNC</code></a>. |
| </p> |
| <p> |
| When an iterator was pushed on <em class="parameter"><code>it</code></em>, it will automatically be popped again |
| with this function. |
| </p> |
| <p> |
| MT safe. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody><tr> |
| <td><p><span class="term"><em class="parameter"><code>it</code></em> :</span></p></td> |
| <td>The <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to resync</td> |
| </tr></tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-iterator-push"></a><h3>gst_iterator_push ()</h3> |
| <pre class="programlisting"><span class="returnvalue">void</span> gst_iterator_push (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *other</code></em>);</pre> |
| <p> |
| Pushes <em class="parameter"><code>other</code></em> iterator onto <em class="parameter"><code>it</code></em>. All calls performed on <em class="parameter"><code>it</code></em> are |
| forwarded to <em class="parameter"><code>other</code></em>. If <em class="parameter"><code>other</code></em> returns <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-DONE:CAPS"><code class="literal">GST_ITERATOR_DONE</code></a>, it is |
| popped again and calls are handled by <em class="parameter"><code>it</code></em> again. |
| </p> |
| <p> |
| This function is mainly used by objects implementing the iterator |
| next function to recurse into substructures. |
| </p> |
| <p> |
| When <a class="link" href="gstreamer-GstIterator.html#gst-iterator-resync" title="gst_iterator_resync ()"><code class="function">gst_iterator_resync()</code></a> is called on <em class="parameter"><code>it</code></em>, <em class="parameter"><code>other</code></em> will automatically be |
| popped. |
| </p> |
| <p> |
| MT safe. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>it</code></em> :</span></p></td> |
| <td>The <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to use</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>other</code></em> :</span></p></td> |
| <td>The <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to push</td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-iterator-filter"></a><h3>gst_iterator_filter ()</h3> |
| <pre class="programlisting"><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="returnvalue">GstIterator</span></a> * gst_iterator_filter (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Doubly-Linked-Lists.html#GCompareFunc"><span class="type">GCompareFunc</span></a> func</code></em>, |
| <em class="parameter"><code>const <a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> *user_data</code></em>);</pre> |
| <p> |
| Create a new iterator from an existing iterator. The new iterator |
| will only return those elements that match the given compare function <em class="parameter"><code>func</code></em>. |
| The first parameter that is passed to <em class="parameter"><code>func</code></em> is the <a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> of the current |
| iterator element and the second parameter is <em class="parameter"><code>user_data</code></em>. <em class="parameter"><code>func</code></em> should |
| return 0 for elements that should be included in the filtered iterator. |
| </p> |
| <p> |
| When this iterator is freed, <em class="parameter"><code>it</code></em> will also be freed. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>it</code></em> :</span></p></td> |
| <td>The <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to filter</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>func</code></em> :</span></p></td> |
| <td>the compare function to select elements. <span class="annotation">[<acronym title="The callback is valid only during the call to the method."><span class="acronym">scope call</span></acronym>]</span> |
| </td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>user_data</code></em> :</span></p></td> |
| <td>user data passed to the compare function. <span class="annotation">[<acronym title="This parameter is a 'user_data', for callbacks; many bindings can pass NULL here."><span class="acronym">closure</span></acronym>]</span> |
| </td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td>a new <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a>. |
| MT safe. <span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>]</span> |
| </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-iterator-fold"></a><h3>gst_iterator_fold ()</h3> |
| <pre class="programlisting"><a class="link" href="gstreamer-GstIterator.html#GstIteratorResult" title="enum GstIteratorResult"><span class="returnvalue">GstIteratorResult</span></a> gst_iterator_fold (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorFoldFunction" title="GstIteratorFoldFunction ()"><span class="type">GstIteratorFoldFunction</span></a> func</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> *ret</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gpointer"><span class="type">gpointer</span></a> user_data</code></em>);</pre> |
| <p> |
| Folds <em class="parameter"><code>func</code></em> over the elements of <em class="parameter"><code>iter</code></em>. That is to say, <em class="parameter"><code>func</code></em> will be called |
| as <em class="parameter"><code>func</code></em> (object, <em class="parameter"><code>ret</code></em>, <em class="parameter"><code>user_data</code></em>) for each object in <em class="parameter"><code>it</code></em>. The normal use |
| of this procedure is to accumulate the results of operating on the objects in |
| <em class="parameter"><code>ret</code></em>. |
| </p> |
| <p> |
| This procedure can be used (and is used internally) to implement the |
| <a class="link" href="gstreamer-GstIterator.html#gst-iterator-foreach" title="gst_iterator_foreach ()"><code class="function">gst_iterator_foreach()</code></a> and <a class="link" href="gstreamer-GstIterator.html#gst-iterator-find-custom" title="gst_iterator_find_custom ()"><code class="function">gst_iterator_find_custom()</code></a> operations. |
| </p> |
| <p> |
| The fold will proceed as long as <em class="parameter"><code>func</code></em> returns TRUE. When the iterator has no |
| more arguments, <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-DONE:CAPS"><code class="literal">GST_ITERATOR_DONE</code></a> will be returned. If <em class="parameter"><code>func</code></em> returns FALSE, |
| the fold will stop, and <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-OK:CAPS"><code class="literal">GST_ITERATOR_OK</code></a> will be returned. Errors or resyncs |
| will cause fold to return <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-ERROR:CAPS"><code class="literal">GST_ITERATOR_ERROR</code></a> or <a class="link" href="gstreamer-GstIterator.html#GST-ITERATOR-RESYNC:CAPS"><code class="literal">GST_ITERATOR_RESYNC</code></a> as |
| appropriate. |
| </p> |
| <p> |
| The iterator will not be freed. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>it</code></em> :</span></p></td> |
| <td>The <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to fold over</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>func</code></em> :</span></p></td> |
| <td>the fold function. <span class="annotation">[<acronym title="The callback is valid only during the call to the method."><span class="acronym">scope call</span></acronym>]</span> |
| </td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>ret</code></em> :</span></p></td> |
| <td>the seed value passed to the fold function</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>user_data</code></em> :</span></p></td> |
| <td>user data passed to the fold function. <span class="annotation">[<acronym title="This parameter is a 'user_data', for callbacks; many bindings can pass NULL here."><span class="acronym">closure</span></acronym>]</span> |
| </td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td>A <a class="link" href="gstreamer-GstIterator.html#GstIteratorResult" title="enum GstIteratorResult"><span class="type">GstIteratorResult</span></a>, as described above. |
| MT safe.</td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-iterator-foreach"></a><h3>gst_iterator_foreach ()</h3> |
| <pre class="programlisting"><a class="link" href="gstreamer-GstIterator.html#GstIteratorResult" title="enum GstIteratorResult"><span class="returnvalue">GstIteratorResult</span></a> gst_iterator_foreach (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>, |
| <em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIteratorForeachFunction" title="GstIteratorForeachFunction ()"><span class="type">GstIteratorForeachFunction</span></a> func</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gpointer"><span class="type">gpointer</span></a> user_data</code></em>);</pre> |
| <p> |
| Iterate over all element of <em class="parameter"><code>it</code></em> and call the given function <em class="parameter"><code>func</code></em> for |
| each element. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>it</code></em> :</span></p></td> |
| <td>The <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to iterate</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>func</code></em> :</span></p></td> |
| <td>the function to call for each element. <span class="annotation">[<acronym title="The callback is valid only during the call to the method."><span class="acronym">scope call</span></acronym>]</span> |
| </td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>user_data</code></em> :</span></p></td> |
| <td>user data passed to the function. <span class="annotation">[<acronym title="This parameter is a 'user_data', for callbacks; many bindings can pass NULL here."><span class="acronym">closure</span></acronym>]</span> |
| </td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td>the result call to <a class="link" href="gstreamer-GstIterator.html#gst-iterator-fold" title="gst_iterator_fold ()"><code class="function">gst_iterator_fold()</code></a>. The iterator will not be |
| freed. |
| MT safe.</td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| <hr> |
| <div class="refsect2"> |
| <a name="gst-iterator-find-custom"></a><h3>gst_iterator_find_custom ()</h3> |
| <pre class="programlisting"><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gboolean"><span class="returnvalue">gboolean</span></a> gst_iterator_find_custom (<em class="parameter"><code><a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> *it</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Doubly-Linked-Lists.html#GCompareFunc"><span class="type">GCompareFunc</span></a> func</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> *elem</code></em>, |
| <em class="parameter"><code><a href="http://library.gnome.org/devel/glib/unstable/glib-Basic-Types.html#gpointer"><span class="type">gpointer</span></a> user_data</code></em>);</pre> |
| <p> |
| Find the first element in <em class="parameter"><code>it</code></em> that matches the compare function <em class="parameter"><code>func</code></em>. |
| <em class="parameter"><code>func</code></em> should return 0 when the element is found. The first parameter |
| to <em class="parameter"><code>func</code></em> will be the current element of the iterator and the |
| second parameter will be <em class="parameter"><code>user_data</code></em>. |
| The result will be stored in <em class="parameter"><code>elem</code></em> if a result is found. |
| </p> |
| <p> |
| The iterator will not be freed. |
| </p> |
| <p> |
| This function will return FALSE if an error happened to the iterator |
| or if the element wasn't found. |
| </p> |
| <div class="variablelist"><table border="0"> |
| <col align="left" valign="top"> |
| <tbody> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>it</code></em> :</span></p></td> |
| <td>The <a class="link" href="gstreamer-GstIterator.html#GstIterator" title="struct GstIterator"><span class="type">GstIterator</span></a> to iterate</td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>func</code></em> :</span></p></td> |
| <td>the compare function to use. <span class="annotation">[<acronym title="The callback is valid only during the call to the method."><span class="acronym">scope call</span></acronym>]</span> |
| </td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>elem</code></em> :</span></p></td> |
| <td>pointer to a <a href="http://library.gnome.org/devel/gobject/unstable/gobject-Generic-values.html#GValue"><span class="type">GValue</span></a> where to store the result. <span class="annotation">[<acronym title="Parameter for returning results. Default is transfer full."><span class="acronym">out</span></acronym>]</span> |
| </td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><em class="parameter"><code>user_data</code></em> :</span></p></td> |
| <td>user data passed to the compare function. <span class="annotation">[<acronym title="This parameter is a 'user_data', for callbacks; many bindings can pass NULL here."><span class="acronym">closure</span></acronym>]</span> |
| </td> |
| </tr> |
| <tr> |
| <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td> |
| <td>Returns TRUE if the element was found, else FALSE. |
| MT safe.</td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
| </div> |
| <div class="refsect1"> |
| <a name="gstreamer-GstIterator.see-also"></a><h2>See Also</h2> |
| <a class="link" href="GstElement.html" title="GstElement"><span class="type">GstElement</span></a>, <a class="link" href="GstBin.html" title="GstBin"><span class="type">GstBin</span></a> |
| </div> |
| </div> |
| <div class="footer"> |
| <hr> |
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