diff options
Diffstat (limited to 'libs/cairo-1.16.0/doc/public/html/bindings-streams.html')
| -rw-r--r-- | libs/cairo-1.16.0/doc/public/html/bindings-streams.html | 91 |
1 files changed, 0 insertions, 91 deletions
diff --git a/libs/cairo-1.16.0/doc/public/html/bindings-streams.html b/libs/cairo-1.16.0/doc/public/html/bindings-streams.html deleted file mode 100644 index ab8d3fc..0000000 --- a/libs/cairo-1.16.0/doc/public/html/bindings-streams.html +++ /dev/null @@ -1,91 +0,0 @@ -<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> -<html> -<head> -<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> -<title>Streams and File I/O: Cairo: A Vector Graphics Library</title> -<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> -<link rel="home" href="index.html" title="Cairo: A Vector Graphics Library"> -<link rel="up" href="language-bindings.html" title="Appendix A. Creating a language binding for cairo"> -<link rel="prev" href="bindings-overloading.html" title="Overloading and optional arguments"> -<link rel="next" href="bindings-errors.html" title="Error handling"> -<meta name="generator" content="GTK-Doc V1.27 (XML mode)"> -<link rel="stylesheet" href="style.css" type="text/css"> -</head> -<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> -<table class="navigation" id="top" width="100%" summary="Navigation header" cellpadding="2" cellspacing="5"><tr valign="middle"> -<td width="100%" align="left" class="shortcuts"></td> -<td><a accesskey="h" href="index.html"><img src="home.png" width="16" height="16" border="0" alt="Home"></a></td> -<td><a accesskey="u" href="language-bindings.html"><img src="up.png" width="16" height="16" border="0" alt="Up"></a></td> -<td><a accesskey="p" href="bindings-overloading.html"><img src="left.png" width="16" height="16" border="0" alt="Prev"></a></td> -<td><a accesskey="n" href="bindings-errors.html"><img src="right.png" width="16" height="16" border="0" alt="Next"></a></td> -</tr></table> -<div class="sect1"> -<div class="titlepage"><div><div><h2 class="title" style="clear: both"> -<a name="bindings-streams"></a>Streams and File I/O</h2></div></div></div> -<p> - Various places in the cairo API deal with reading and writing - data, whether from and to files, or to other sources and - destinations. In these cases, what is typically provided in the - C API is a simple version that just takes a filename, and a - complex version that takes a callback function. - An example is the PNG handling functions: - </p> -<pre class="programlisting"> -cairo_surface_t * -cairo_image_surface_create_from_png (const char *filename); - -cairo_surface_t * -cairo_image_surface_create_from_png_stream (cairo_read_func_t read_func, - void *closure); - -cairo_status_t -cairo_surface_write_to_png (cairo_surface_t *surface, - const char *filename); - -cairo_status_t -cairo_surface_write_to_png_stream (cairo_surface_t *surface, - cairo_write_func_t write_func, - void *closure);</pre> -<p> - The expectation is that the filename version will be mapped - literally in the language binding, but the callback version - will be mapped to a version that takes a language stream - object. For example, in Java, the four functions above - might be mapped to: - </p> -<pre class="programlisting"> -static public ImageSurface createFromPNG (String filename) throws IOException; -static public ImageSurface createFromPNG (InputStream stream) throws IOException; -public void writeToPNG (String filename) throws IOException; -public void writeToPNG (OutputStream stream) throws IOException; -</pre> -<p> - In many cases, it will be better to - implement the filename version internally - using the stream version, rather than building it on top of the - filename version in C. The reason for this is that will - naturally give a more standard handling of file errors for - the language, as seen in the above Java example, where - <code class="methodname">createFromPNG()</code> is marked as raising - an exception. Propagating exceptions from inside the callback - function to the caller will pose a challenge to the language - binding implementor, since an exception must not propagate - through the Cairo code. A technique that will be useful in - some cases is to catch the exception in the callback, - store the exception object inside a structure pointed to by - <em class="parameter"><code>closure</code></em>, and then rethrow it once - the function returns. - </p> -<p class="remark"><em><span class="remark"> - I'm not sure how to handle this for - <a class="link" href="cairo-PDF-Surfaces.html#cairo-pdf-surface-create-for-stream" title="cairo_pdf_surface_create_for_stream ()"><code class="function">cairo_pdf_surface_create_for_stream()</code></a>. - Other than keep a “exception to rethrow” thread-specific - variable - that is checked after <span class="emphasis"><em>every</em></span> call to a Cairo - function. - </span></em></p> -</div> -<div class="footer"> -<hr>Generated by GTK-Doc V1.27</div> -</body> -</html>
\ No newline at end of file |