1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 2<html> 3<!-- Copyright (C) 1988-2021 Free Software Foundation, Inc. 4 5Permission is granted to copy, distribute and/or modify this document 6under the terms of the GNU Free Documentation License, Version 1.3 or 7any later version published by the Free Software Foundation; with the 8Invariant Sections being "Free Software" and "Free Software Needs 9Free Documentation", with the Front-Cover Texts being "A GNU Manual," 10and with the Back-Cover Texts as in (a) below. 11 12(a) The FSF's Back-Cover Text is: "You are free to copy and modify 13this GNU Manual. 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The underlying breakpoint will be disabled 79and deleted when the execution will run out of the breakpoint scope (i.e. 80<code>Breakpoint.stop</code> or <code>FinishBreakpoint.out_of_scope</code> triggered). 81Finish breakpoints are thread specific and must be create with the right 82thread selected. 83</p> 84<dl> 85<dt><a name="index-FinishBreakpoint_002e_005f_005finit_005f_005f"></a>Function: <strong>FinishBreakpoint.__init__</strong> <em>(<span class="roman">[</span>frame<span class="roman">]</span> <span class="roman">[</span>, internal<span class="roman">]</span>)</em></dt> 86<dd><p>Create a finish breakpoint at the return address of the <code>gdb.Frame</code> 87object <var>frame</var>. If <var>frame</var> is not provided, this defaults to the 88newest frame. The optional <var>internal</var> argument allows the breakpoint to 89become invisible to the user. See <a href="Breakpoints-In-Python.html#Breakpoints-In-Python">Breakpoints In Python</a>, for further 90details about this argument. 91</p></dd></dl> 92 93<dl> 94<dt><a name="index-FinishBreakpoint_002eout_005fof_005fscope"></a>Function: <strong>FinishBreakpoint.out_of_scope</strong> <em>(self)</em></dt> 95<dd><p>In some circumstances (e.g. <code>longjmp</code>, C<tt>++</tt> exceptions, <small>GDB</small> 96<code>return</code> command, …), a function may not properly terminate, and 97thus never hit the finish breakpoint. When <small>GDB</small> notices such a 98situation, the <code>out_of_scope</code> callback will be triggered. 99</p> 100<p>You may want to sub-class <code>gdb.FinishBreakpoint</code> and override this 101method: 102</p> 103<div class="smallexample"> 104<pre class="smallexample">class MyFinishBreakpoint (gdb.FinishBreakpoint) 105 def stop (self): 106 print "normal finish" 107 return True 108 109 def out_of_scope (): 110 print "abnormal finish" 111</pre></div> 112</dd></dl> 113 114<dl> 115<dt><a name="index-FinishBreakpoint_002ereturn_005fvalue"></a>Variable: <strong>FinishBreakpoint.return_value</strong></dt> 116<dd><p>When <small>GDB</small> is stopped at a finish breakpoint and the frame 117used to build the <code>gdb.FinishBreakpoint</code> object had debug symbols, this 118attribute will contain a <code>gdb.Value</code> object corresponding to the return 119value of the function. The value will be <code>None</code> if the function return 120type is <code>void</code> or if the return value was not computable. This attribute 121is not writable. 122</p></dd></dl> 123 124<hr> 125<div class="header"> 126<p> 127Next: <a href="Lazy-Strings-In-Python.html#Lazy-Strings-In-Python" accesskey="n" rel="next">Lazy Strings In Python</a>, Previous: <a href="Breakpoints-In-Python.html#Breakpoints-In-Python" accesskey="p" rel="previous">Breakpoints In Python</a>, Up: <a href="Python-API.html#Python-API" accesskey="u" rel="up">Python API</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p> 128</div> 129 130 131 132</body> 133</html> 134