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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This can be accomplished by means of the 85‘<samp>QStartNoAckMode</samp>’ packet; see <a href="General-Query-Packets.html#QStartNoAckMode">QStartNoAckMode</a>. 86</p> 87<p>When in no-acknowledgment mode, neither the stub nor <small>GDB</small> shall send or 88expect ‘<samp>+</samp>’/‘<samp>-</samp>’ protocol acknowledgments. The packet 89and response format still includes the normal checksum, as described in 90<a href="Overview.html#Overview">Overview</a>, but the checksum may be ignored by the receiver. 91</p> 92<p>If the stub supports ‘<samp>QStartNoAckMode</samp>’ and prefers to operate in 93no-acknowledgment mode, it should report that to <small>GDB</small> 94by including ‘<samp>QStartNoAckMode+</samp>’ in its response to ‘<samp>qSupported</samp>’; 95see <a href="General-Query-Packets.html#qSupported">qSupported</a>. 96If <small>GDB</small> also supports ‘<samp>QStartNoAckMode</samp>’ and it has not been 97disabled via the <code>set remote noack-packet off</code> command 98(see <a href="Remote-Configuration.html#Remote-Configuration">Remote Configuration</a>), 99<small>GDB</small> may then send a ‘<samp>QStartNoAckMode</samp>’ packet to the stub. 100Only then may the stub actually turn off packet acknowledgments. 101<small>GDB</small> sends a final ‘<samp>+</samp>’ acknowledgment of the stub’s ‘<samp>OK</samp>’ 102response, which can be safely ignored by the stub. 103</p> 104<p>Note that <code>set remote noack-packet</code> command only affects negotiation 105between <small>GDB</small> and the stub when subsequent connections are made; 106it does not affect the protocol acknowledgment state for any current 107connection. 108Since ‘<samp>+</samp>’/‘<samp>-</samp>’ acknowledgments are enabled by default when a 109new connection is established, 110there is also no protocol request to re-enable the acknowledgments 111for the current connection, once disabled. 112</p> 113<hr> 114<div class="header"> 115<p> 116Next: <a href="Examples.html#Examples" accesskey="n" rel="next">Examples</a>, Previous: <a href="Remote-Non_002dStop.html#Remote-Non_002dStop" accesskey="p" rel="previous">Remote Non-Stop</a>, Up: <a href="Remote-Protocol.html#Remote-Protocol" accesskey="u" rel="up">Remote Protocol</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> 117</div> 118 119 120 121</body> 122</html> 123