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<center><h1>FreeType-2.1.10 API Reference</h1></center>
<center><h1>
System Interface
</h1></center>
<h2>Synopsis</h2>
<table align=center cellspacing=5 cellpadding=0 border=0>
<tr><td></td><td><a href="#FT_Memory">FT_Memory</a></td><td></td><td><a href="#FT_MemoryRec">FT_MemoryRec</a></td><td></td><td><a href="#FT_Stream_CloseFunc">FT_Stream_CloseFunc</a></td></tr>
<tr><td></td><td><a href="#FT_Alloc_Func">FT_Alloc_Func</a></td><td></td><td><a href="#FT_Stream">FT_Stream</a></td><td></td><td><a href="#FT_StreamRec">FT_StreamRec</a></td></tr>
<tr><td></td><td><a href="#FT_Free_Func">FT_Free_Func</a></td><td></td><td><a href="#FT_StreamDesc">FT_StreamDesc</a></td><td></td><td></td></tr>
<tr><td></td><td><a href="#FT_Realloc_Func">FT_Realloc_Func</a></td><td></td><td><a href="#FT_Stream_IoFunc">FT_Stream_IoFunc</a></td><td></td><td></td></tr>
</table><br><br>
<table align=center width="87%"><tr><td>
<p>This section contains various definitions related to memory management and i/o access. You need to understand this information if you want to use a custom memory manager or you own input i/o streams.</p>
</td></tr></table><br>
<table align=center width="75%"><tr><td>
<h4><a name="FT_Memory">FT_Memory</a></h4>
<table align=center width="87%"><tr bgcolor="#D6E8FF"><td><pre>
<span class="keyword">typedef</span> <span class="keyword">struct</span> FT_MemoryRec_* <b>FT_Memory</b>;
</pre></table><br>
<table align=center width="87%"><tr><td>
<p>A handle to a given memory manager object, defined with a <a href="ft2-system_interface.html#FT_MemoryRec">FT_MemoryRec</a> structure.</p>
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</td></tr></table><hr width="75%">
<table align=center width="75%"><tr><td>
<h4><a name="FT_Alloc_Func">FT_Alloc_Func</a></h4>
<table align=center width="87%"><tr bgcolor="#D6E8FF"><td><pre>
<span class="keyword">typedef</span> <span class="keyword">void</span>*
(*<b>FT_Alloc_Func</b>)( <a href="ft2-system_interface.html#FT_Memory">FT_Memory</a> memory,
<span class="keyword">long</span> size );
</pre></table><br>
<table align=center width="87%"><tr><td>
<p>A function used to allocate `size' bytes from `memory'.</p>
</td></tr></table><br>
<table align=center width="87%" cellpadding=5><tr bgcolor="#EEEEFF"><td><em><b>input</b></em></td></tr><tr><td>
<table cellpadding=3>
<tr valign=top><td><b>memory</b></td><td>
<p>A handle to the source memory manager.</p>
</td></tr>
<tr valign=top><td><b>size</b></td><td>
<p>The size in bytes to allocate.</p>
</td></tr>
</table>
</td></tr></table>
<table align=center width="87%" cellpadding=5><tr bgcolor="#EEEEFF"><td><em><b>return</b></em></td></tr><tr><td>
<p>Address of new memory block. 0 in case of failure.</p>
</td></tr></table>
</td></tr></table><hr width="75%">
<table align=center width="75%"><tr><td>
<h4><a name="FT_Free_Func">FT_Free_Func</a></h4>
<table align=center width="87%"><tr bgcolor="#D6E8FF"><td><pre>
<span class="keyword">typedef</span> <span class="keyword">void</span>
(*<b>FT_Free_Func</b>)( <a href="ft2-system_interface.html#FT_Memory">FT_Memory</a> memory,
<span class="keyword">void</span>* block );
</pre></table><br>
<table align=center width="87%"><tr><td>
<p>A function used to release a given block of memory.</p>
</td></tr></table><br>
<table align=center width="87%" cellpadding=5><tr bgcolor="#EEEEFF"><td><em><b>input</b></em></td></tr><tr><td>
<table cellpadding=3>
<tr valign=top><td><b>memory</b></td><td>
<p>A handle to the source memory manager.</p>
</td></tr>
<tr valign=top><td><b>block</b></td><td>
<p>The address of the target memory block.</p>
</td></tr>
</table>
</td></tr></table>
</td></tr></table><hr width="75%">
<table align=center width="75%"><tr><td>
<h4><a name="FT_Realloc_Func">FT_Realloc_Func</a></h4>
<table align=center width="87%"><tr bgcolor="#D6E8FF"><td><pre>
<span class="keyword">typedef</span> <span class="keyword">void</span>*
(*<b>FT_Realloc_Func</b>)( <a href="ft2-system_interface.html#FT_Memory">FT_Memory</a> memory,
<span class="keyword">long</span> cur_size,
<span class="keyword">long</span> new_size,
<span class="keyword">void</span>* block );
</pre></table><br>
<table align=center width="87%"><tr><td>
<p>a function used to re-allocate a given block of memory.</p>
</td></tr></table><br>
<table align=center width="87%" cellpadding=5><tr bgcolor="#EEEEFF"><td><em><b>input</b></em></td></tr><tr><td>
<table cellpadding=3>
<tr valign=top><td><b>memory</b></td><td>
<p>A handle to the source memory manager.</p>
</td></tr>
<tr valign=top><td><b>cur_size</b></td><td>
<p>The block's current size in bytes.</p>
</td></tr>
<tr valign=top><td><b>new_size</b></td><td>
<p>The block's requested new size.</p>
</td></tr>
<tr valign=top><td><b>block</b></td><td>
<p>The block's current address.</p>
</td></tr>
</table>
</td></tr></table>
<table align=center width="87%" cellpadding=5><tr bgcolor="#EEEEFF"><td><em><b>return</b></em></td></tr><tr><td>
<p>New block address. 0 in case of memory shortage.</p>
</td></tr></table>
<table align=center width="87%" cellpadding=5><tr bgcolor="#EEEEFF"><td><em><b>note</b></em></td></tr><tr><td>
<p>In case of error, the old block must still be available.</p>
</td></tr></table>
</td></tr></table><hr width="75%">
<table align=center width="75%"><tr><td>
<h4><a name="FT_MemoryRec">FT_MemoryRec</a></h4>
<table align=center width="87%"><tr bgcolor="#D6E8FF"><td><pre>
<span class="keyword">struct</span> FT_MemoryRec_
{
<span class="keyword">void</span>* user;
<a href="ft2-system_interface.html#FT_Alloc_Func">FT_Alloc_Func</a> alloc;
<a href="ft2-system_interface.html#FT_Free_Func">FT_Free_Func</a> free;
<a href="ft2-system_interface.html#FT_Realloc_Func">FT_Realloc_Func</a> realloc;
};
</pre></table><br>
<table align=center width="87%"><tr><td>
<p>A structure used to describe a given memory manager to FreeType 2.</p>
</td></tr></table><br>
<table align=center width="87%" cellpadding=5><tr bgcolor="#EEEEFF"><td><em><b>fields</b></em></td></tr><tr><td>
<table cellpadding=3>
<tr valign=top><td><b>user</b></td><td>
<p>A generic typeless pointer for user data.</p>
</td></tr>
<tr valign=top><td><b>alloc</b></td><td>
<p>A pointer type to an allocation function.</p>
</td></tr>
<tr valign=top><td><b>free</b></td><td>
<p>A pointer type to an memory freeing function.</p>
</td></tr>
<tr valign=top><td><b>realloc</b></td><td>
<p>A pointer type to a reallocation function.</p>
</td></tr>
</table>
</td></tr></table>
</td></tr></table><hr width="75%">
<table align=center width="75%"><tr><td>
<h4><a name="FT_Stream">FT_Stream</a></h4>
<table align=center width="87%"><tr bgcolor="#D6E8FF"><td><pre>
<span class="keyword">typedef</span> <span class="keyword">struct</span> FT_StreamRec_* <b>FT_Stream</b>;
</pre></table><br>
<table align=center width="87%"><tr><td>
<p>A handle to an input stream.</p>
</td></tr></table><br>
</td></tr></table><hr width="75%">
<table align=center width="75%"><tr><td>
<h4><a name="FT_StreamDesc">FT_StreamDesc</a></h4>
<table align=center width="87%"><tr bgcolor="#D6E8FF"><td><pre>
<span class="keyword">typedef</span> <span class="keyword">union</span> FT_StreamDesc_
{
<span class="keyword">long</span> value;
<span class="keyword">void</span>* pointer;
} <b>FT_StreamDesc</b>;
</pre></table><br>
<table align=center width="87%"><tr><td>
<p>A union type used to store either a long or a pointer. This is used to store a file descriptor or a FILE* in an input stream.</p>
</td></tr></table><br>
</td></tr></table><hr width="75%">
<table align=center width="75%"><tr><td>
<h4><a name="FT_Stream_IoFunc">FT_Stream_IoFunc</a></h4>
<table align=center width="87%"><tr bgcolor="#D6E8FF"><td><pre>
<span class="keyword">typedef</span> <span class="keyword">unsigned</span> <span class="keyword">long</span>
(*<b>FT_Stream_IoFunc</b>)( <a href="ft2-system_interface.html#FT_Stream">FT_Stream</a> stream,
<span class="keyword">unsigned</span> <span class="keyword">long</span> offset,
<span class="keyword">unsigned</span> <span class="keyword">char</span>* buffer,
<span class="keyword">unsigned</span> <span class="keyword">long</span> count );
</pre></table><br>
<table align=center width="87%"><tr><td>
<p>A function used to seek and read data from a given input stream.</p>
</td></tr></table><br>
<table align=center width="87%" cellpadding=5><tr bgcolor="#EEEEFF"><td><em><b>input</b></em></td></tr><tr><td>
<table cellpadding=3>
<tr valign=top><td><b>stream</b></td><td>
<p>A handle to the source stream.</p>
</td></tr>
<tr valign=top><td><b>offset</b></td><td>
<p>The offset of read in stream (always from start).</p>
</td></tr>
<tr valign=top><td><b>buffer</b></td><td>
<p>The address of the read buffer.</p>
</td></tr>
<tr valign=top><td><b>count</b></td><td>
<p>The number of bytes to read from the stream.</p>
</td></tr>
</table>
</td></tr></table>
<table align=center width="87%" cellpadding=5><tr bgcolor="#EEEEFF"><td><em><b>return</b></em></td></tr><tr><td>
<p>The number of bytes effectively read by the stream.</p>
</td></tr></table>
<table align=center width="87%" cellpadding=5><tr bgcolor="#EEEEFF"><td><em><b>note</b></em></td></tr><tr><td>
<p>This function might be called to perform a seek or skip operation with a `count' of 0.</p>
</td></tr></table>
</td></tr></table><hr width="75%">
<table align=center width="75%"><tr><td>
<h4><a name="FT_Stream_CloseFunc">FT_Stream_CloseFunc</a></h4>
<table align=center width="87%"><tr bgcolor="#D6E8FF"><td><pre>
<span class="keyword">typedef</span> <span class="keyword">void</span>
(*<b>FT_Stream_CloseFunc</b>)( <a href="ft2-system_interface.html#FT_Stream">FT_Stream</a> stream );
</pre></table><br>
<table align=center width="87%"><tr><td>
<p>A function used to close a given input stream.</p>
</td></tr></table><br>
<table align=center width="87%" cellpadding=5><tr bgcolor="#EEEEFF"><td><em><b>input</b></em></td></tr><tr><td>
<table cellpadding=3>
<tr valign=top><td><b>stream</b></td><td>
<p>A handle to the target stream.</p>
</td></tr>
</table>
</td></tr></table>
</td></tr></table><hr width="75%">
<table align=center width="75%"><tr><td>
<h4><a name="FT_StreamRec">FT_StreamRec</a></h4>
<table align=center width="87%"><tr bgcolor="#D6E8FF"><td><pre>
<span class="keyword">typedef</span> <span class="keyword">struct</span> FT_StreamRec_
{
<span class="keyword">unsigned</span> <span class="keyword">char</span>* base;
<span class="keyword">unsigned</span> <span class="keyword">long</span> size;
<span class="keyword">unsigned</span> <span class="keyword">long</span> pos;
<a href="ft2-system_interface.html#FT_StreamDesc">FT_StreamDesc</a> descriptor;
<a href="ft2-system_interface.html#FT_StreamDesc">FT_StreamDesc</a> pathname;
<a href="ft2-system_interface.html#FT_Stream_IoFunc">FT_Stream_IoFunc</a> read;
<a href="ft2-system_interface.html#FT_Stream_CloseFunc">FT_Stream_CloseFunc</a> close;
<a href="ft2-system_interface.html#FT_Memory">FT_Memory</a> memory;
<span class="keyword">unsigned</span> <span class="keyword">char</span>* cursor;
<span class="keyword">unsigned</span> <span class="keyword">char</span>* limit;
} <b>FT_StreamRec</b>;
</pre></table><br>
<table align=center width="87%"><tr><td>
<p>A structure used to describe an input stream.</p>
</td></tr></table><br>
<table align=center width="87%" cellpadding=5><tr bgcolor="#EEEEFF"><td><em><b>input</b></em></td></tr><tr><td>
<table cellpadding=3>
<tr valign=top><td><b>base</b></td><td>
<p>For memory-based streams, this is the address of the first stream byte in memory. This field should always be set to NULL for disk-based streams.</p>
</td></tr>
<tr valign=top><td><b>size</b></td><td>
<p>The stream size in bytes.</p>
</td></tr>
<tr valign=top><td><b>pos</b></td><td>
<p>The current position within the stream.</p>
</td></tr>
<tr valign=top><td><b>descriptor</b></td><td>
<p>This field is a union that can hold an integer or a pointer. It is used by stream implementations to store file descriptors or FILE* pointers.</p>
</td></tr>
<tr valign=top><td><b>pathname</b></td><td>
<p>This field is completely ignored by FreeType. However, it is often useful during debugging to use it to store the stream's filename (where available).</p>
</td></tr>
<tr valign=top><td><b>read</b></td><td>
<p>The stream's input function.</p>
</td></tr>
<tr valign=top><td><b>close</b></td><td>
<p>The stream;s close function.</p>
</td></tr>
<tr valign=top><td><b>memory</b></td><td>
<p>The memory manager to use to preload frames. This is set internally by FreeType and shouldn't be touched by stream implementations.</p>
</td></tr>
<tr valign=top><td><b>cursor</b></td><td>
<p>This field is set and used internally by FreeType when parsing frames.</p>
</td></tr>
<tr valign=top><td><b>limit</b></td><td>
<p>This field is set and used internally by FreeType when parsing frames.</p>
</td></tr>
</table>
</td></tr></table>
</td></tr></table><hr width="75%">
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