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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There 81are two modes of controlling execution of your program within the 82debugger. In the default mode, referred to as <em>all-stop mode</em>, 83when any thread in your program stops (for example, at a breakpoint 84or while being stepped), all other threads in the program are also stopped by 85<small>GDB</small>. On some targets, <small>GDB</small> also supports 86<em>non-stop mode</em>, in which other threads can continue to run freely while 87you examine the stopped thread in the debugger. 88</p> 89<table class="menu" border="0" cellspacing="0"> 90<tr><td align="left" valign="top">• <a href="All_002dStop-Mode.html#All_002dStop-Mode" accesskey="1">All-Stop Mode</a>:</td><td> </td><td align="left" valign="top">All threads stop when GDB takes control 91</td></tr> 92<tr><td align="left" valign="top">• <a href="Non_002dStop-Mode.html#Non_002dStop-Mode" accesskey="2">Non-Stop Mode</a>:</td><td> </td><td align="left" valign="top">Other threads continue to execute 93</td></tr> 94<tr><td align="left" valign="top">• <a href="Background-Execution.html#Background-Execution" accesskey="3">Background Execution</a>:</td><td> </td><td align="left" valign="top">Running your program asynchronously 95</td></tr> 96<tr><td align="left" valign="top">• <a href="Thread_002dSpecific-Breakpoints.html#Thread_002dSpecific-Breakpoints" accesskey="4">Thread-Specific Breakpoints</a>:</td><td> </td><td align="left" valign="top">Controlling breakpoints 97</td></tr> 98<tr><td align="left" valign="top">• <a href="Interrupted-System-Calls.html#Interrupted-System-Calls" accesskey="5">Interrupted System Calls</a>:</td><td> </td><td align="left" valign="top">GDB may interfere with system calls 99</td></tr> 100<tr><td align="left" valign="top">• <a href="Observer-Mode.html#Observer-Mode" accesskey="6">Observer Mode</a>:</td><td> </td><td align="left" valign="top">GDB does not alter program behavior 101</td></tr> 102</table> 103 104 105 106 107</body> 108</html> 109