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diff --git a/gcc-4.4.3/libstdc++-v3/doc/html/manual/dynamic_memory.html b/gcc-4.4.3/libstdc++-v3/doc/html/manual/dynamic_memory.html new file mode 100644 index 000000000..2a3d1368b --- /dev/null +++ b/gcc-4.4.3/libstdc++-v3/doc/html/manual/dynamic_memory.html @@ -0,0 +1,69 @@ +<?xml version="1.0" encoding="UTF-8" standalone="no"?> +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> +<html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>Chapter 5. Dynamic Memory</title><meta name="generator" content="DocBook XSL Stylesheets V1.74.0" /><meta name="keywords" content=" ISO C++ , library " /><link rel="home" href="../spine.html" title="The GNU C++ Library Documentation" /><link rel="up" href="support.html" title="Part II. Support" /><link rel="prev" href="bk01pt02ch04s03.html" title="NULL" /><link rel="next" href="termination.html" title="Chapter 6. Termination" /></head><body><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Chapter 5. Dynamic Memory</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="bk01pt02ch04s03.html">Prev</a> </td><th width="60%" align="center">Part II. + Support + +</th><td width="20%" align="right"> <a accesskey="n" href="termination.html">Next</a></td></tr></table><hr /></div><div class="chapter" lang="en" xml:lang="en"><div class="titlepage"><div><div><h2 class="title"><a id="manual.support.memory"></a>Chapter 5. Dynamic Memory</h2></div></div></div><p> + There are six flavors each of <code class="function">new</code> and + <code class="function">delete</code>, so make certain that you're using the right + ones. Here are quickie descriptions of <code class="function">new</code>: + </p><div class="itemizedlist"><ul type="disc"><li><p> + single object form, throwing a + <code class="classname">bad_alloc</code> on errors; this is what most + people are used to using + </p></li><li><p> + Single object "nothrow" form, returning NULL on errors + </p></li><li><p> + Array <code class="function">new</code>, throwing + <code class="classname">bad_alloc</code> on errors + </p></li><li><p> + Array nothrow <code class="function">new</code>, returning + <code class="constant">NULL</code> on errors + </p></li><li><p> + Placement <code class="function">new</code>, which does nothing (like + it's supposed to) + </p></li><li><p> + Placement array <code class="function">new</code>, which also does + nothing + </p></li></ul></div><p> + They are distinguished by the parameters that you pass to them, like + any other overloaded function. The six flavors of <code class="function">delete</code> + are distinguished the same way, but none of them are allowed to throw + an exception under any circumstances anyhow. (They match up for + completeness' sake.) + </p><p> + Remember that it is perfectly okay to call <code class="function">delete</code> on a + NULL pointer! Nothing happens, by definition. That is not the + same thing as deleting a pointer twice. + </p><p> + By default, if one of the “<span class="quote">throwing <code class="function">new</code>s</span>” can't + allocate the memory requested, it tosses an instance of a + <code class="classname">bad_alloc</code> exception (or, technically, some class derived + from it). You can change this by writing your own function (called a + new-handler) and then registering it with <code class="function">set_new_handler()</code>: + </p><pre class="programlisting"> + typedef void (*PFV)(void); + + static char* safety; + static PFV old_handler; + + void my_new_handler () + { + delete[] safety; + popup_window ("Dude, you are running low on heap memory. You + should, like, close some windows, or something. + The next time you run out, we're gonna burn!"); + set_new_handler (old_handler); + return; + } + + int main () + { + safety = new char[500000]; + old_handler = set_new_handler (&my_new_handler); + ... + } + </pre><p> + <code class="classname">bad_alloc</code> is derived from the base <code class="classname">exception</code> + class defined in Chapter 19. + </p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="bk01pt02ch04s03.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="support.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="termination.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">NULL </td><td width="20%" align="center"><a accesskey="h" href="../spine.html">Home</a></td><td width="40%" align="right" valign="top"> Chapter 6. Termination</td></tr></table></div></body></html> |