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diff --git a/share/doc/gdb/CLI-Commands-In-Python.html b/share/doc/gdb/CLI-Commands-In-Python.html new file mode 100644 index 0000000..f635b5a --- /dev/null +++ b/share/doc/gdb/CLI-Commands-In-Python.html @@ -0,0 +1,398 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 1988-2023 Free Software Foundation, Inc. + +Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with the +Invariant Sections being "Free Software" and "Free Software Needs +Free Documentation", with the Front-Cover Texts being "A GNU Manual," +and with the Back-Cover Texts as in (a) below. + +(a) The FSF's Back-Cover Text is: "You are free to copy and modify +this GNU Manual. 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A CLI +command is implemented using an instance of the <code>gdb.Command</code> +class, most commonly using a subclass. +</p> +<dl> +<dt><a name="index-Command_002e_005f_005finit_005f_005f"></a>Function: <strong>Command.__init__</strong> <em>(name, <var>command_class</var> <span class="roman">[</span>, <var>completer_class</var> <span class="roman">[</span>, <var>prefix</var><span class="roman">]]</span>)</em></dt> +<dd><p>The object initializer for <code>Command</code> registers the new command +with <small>GDB</small>. This initializer is normally invoked from the +subclass’ own <code>__init__</code> method. +</p> +<p><var>name</var> is the name of the command. If <var>name</var> consists of +multiple words, then the initial words are looked for as prefix +commands. In this case, if one of the prefix commands does not exist, +an exception is raised. +</p> +<p>There is no support for multi-line commands. +</p> +<p><var>command_class</var> should be one of the ‘<samp>COMMAND_</samp>’ constants +defined below. This argument tells <small>GDB</small> how to categorize the +new command in the help system. +</p> +<p><var>completer_class</var> is an optional argument. If given, it should be +one of the ‘<samp>COMPLETE_</samp>’ constants defined below. This argument +tells <small>GDB</small> how to perform completion for this command. If not +given, <small>GDB</small> will attempt to complete using the object’s +<code>complete</code> method (see below); if no such method is found, an +error will occur when completion is attempted. +</p> +<p><var>prefix</var> is an optional argument. If <code>True</code>, then the new +command is a prefix command; sub-commands of this command may be +registered. +</p> +<p>The help text for the new command is taken from the Python +documentation string for the command’s class, if there is one. If no +documentation string is provided, the default value “This command is +not documented.” is used. +</p></dd></dl> + +<a name="index-don_0027t-repeat-Python-command"></a> +<dl> +<dt><a name="index-Command_002edont_005frepeat"></a>Function: <strong>Command.dont_repeat</strong> <em>()</em></dt> +<dd><p>By default, a <small>GDB</small> command is repeated when the user enters a +blank line at the command prompt. A command can suppress this +behavior by invoking the <code>dont_repeat</code> method at some point in +its <code>invoke</code> method (normally this is done early in case of +exception). This is similar to the user command <code>dont-repeat</code>, +see <a href="Define.html#Define">dont-repeat</a>. +</p></dd></dl> + +<dl> +<dt><a name="index-Command_002einvoke"></a>Function: <strong>Command.invoke</strong> <em>(argument, from_tty)</em></dt> +<dd><p>This method is called by <small>GDB</small> when this command is invoked. +</p> +<p><var>argument</var> is a string. It is the argument to the command, after +leading and trailing whitespace has been stripped. +</p> +<p><var>from_tty</var> is a boolean argument. When true, this means that the +command was entered by the user at the terminal; when false it means +that the command came from elsewhere. +</p> +<p>If this method throws an exception, it is turned into a <small>GDB</small> +<code>error</code> call. Otherwise, the return value is ignored. +</p> +<a name="index-gdb_002estring_005fto_005fargv"></a> +<p>To break <var>argument</var> up into an argv-like string use +<code>gdb.string_to_argv</code>. This function behaves identically to +<small>GDB</small>’s internal argument lexer <code>buildargv</code>. +It is recommended to use this for consistency. +Arguments are separated by spaces and may be quoted. +Example: +</p> +<div class="smallexample"> +<pre class="smallexample">print gdb.string_to_argv ("1 2\ \\\"3 '4 \"5' \"6 '7\"") +['1', '2 "3', '4 "5', "6 '7"] +</pre></div> + +</dd></dl> + +<a name="index-completion-of-Python-commands"></a> +<dl> +<dt><a name="index-Command_002ecomplete"></a>Function: <strong>Command.complete</strong> <em>(text, word)</em></dt> +<dd><p>This method is called by <small>GDB</small> when the user attempts +completion on this command. All forms of completion are handled by +this method, that is, the <tt class="key">TAB</tt> and <tt class="key">M-?</tt> key bindings +(see <a href="Completion.html#Completion">Completion</a>), and the <code>complete</code> command (see <a href="Help.html#Help">complete</a>). +</p> +<p>The arguments <var>text</var> and <var>word</var> are both strings; <var>text</var> +holds the complete command line up to the cursor’s location, while +<var>word</var> holds the last word of the command line; this is computed +using a word-breaking heuristic. +</p> +<p>The <code>complete</code> method can return several values: +</p><ul> +<li> If the return value is a sequence, the contents of the sequence are +used as the completions. It is up to <code>complete</code> to ensure that the +contents actually do complete the word. A zero-length sequence is +allowed, it means that there were no completions available. Only +string elements of the sequence are used; other elements in the +sequence are ignored. + +</li><li> If the return value is one of the ‘<samp>COMPLETE_</samp>’ constants defined +below, then the corresponding <small>GDB</small>-internal completion +function is invoked, and its result is used. + +</li><li> All other results are treated as though there were no available +completions. +</li></ul> +</dd></dl> + +<p>When a new command is registered, it must be declared as a member of +some general class of commands. This is used to classify top-level +commands in the on-line help system; note that prefix commands are not +listed under their own category but rather that of their top-level +command. The available classifications are represented by constants +defined in the <code>gdb</code> module: +</p> +<dl compact="compact"> +<dd><a name="index-COMMAND_005fNONE"></a> +<a name="index-gdb_002eCOMMAND_005fNONE"></a> +</dd> +<dt><code>gdb.COMMAND_NONE</code></dt> +<dd><p>The command does not belong to any particular class. A command in +this category will not be displayed in any of the help categories. +</p> +<a name="index-COMMAND_005fRUNNING"></a> +<a name="index-gdb_002eCOMMAND_005fRUNNING"></a> +</dd> +<dt><code>gdb.COMMAND_RUNNING</code></dt> +<dd><p>The command is related to running the inferior. For example, +<code>start</code>, <code>step</code>, and <code>continue</code> are in this category. +Type <kbd>help running</kbd> at the <small>GDB</small> prompt to see a list of +commands in this category. +</p> +<a name="index-COMMAND_005fDATA"></a> +<a name="index-gdb_002eCOMMAND_005fDATA"></a> +</dd> +<dt><code>gdb.COMMAND_DATA</code></dt> +<dd><p>The command is related to data or variables. For example, +<code>call</code>, <code>find</code>, and <code>print</code> are in this category. Type +<kbd>help data</kbd> at the <small>GDB</small> prompt to see a list of commands +in this category. +</p> +<a name="index-COMMAND_005fSTACK"></a> +<a name="index-gdb_002eCOMMAND_005fSTACK"></a> +</dd> +<dt><code>gdb.COMMAND_STACK</code></dt> +<dd><p>The command has to do with manipulation of the stack. For example, +<code>backtrace</code>, <code>frame</code>, and <code>return</code> are in this +category. Type <kbd>help stack</kbd> at the <small>GDB</small> prompt to see a +list of commands in this category. +</p> +<a name="index-COMMAND_005fFILES"></a> +<a name="index-gdb_002eCOMMAND_005fFILES"></a> +</dd> +<dt><code>gdb.COMMAND_FILES</code></dt> +<dd><p>This class is used for file-related commands. For example, +<code>file</code>, <code>list</code> and <code>section</code> are in this category. +Type <kbd>help files</kbd> at the <small>GDB</small> prompt to see a list of +commands in this category. +</p> +<a name="index-COMMAND_005fSUPPORT"></a> +<a name="index-gdb_002eCOMMAND_005fSUPPORT"></a> +</dd> +<dt><code>gdb.COMMAND_SUPPORT</code></dt> +<dd><p>This should be used for “support facilities”, generally meaning +things that are useful to the user when interacting with <small>GDB</small>, +but not related to the state of the inferior. For example, +<code>help</code>, <code>make</code>, and <code>shell</code> are in this category. Type +<kbd>help support</kbd> at the <small>GDB</small> prompt to see a list of +commands in this category. +</p> +<a name="index-COMMAND_005fSTATUS"></a> +<a name="index-gdb_002eCOMMAND_005fSTATUS"></a> +</dd> +<dt><code>gdb.COMMAND_STATUS</code></dt> +<dd><p>The command is an ‘<samp>info</samp>’-related command, that is, related to the +state of <small>GDB</small> itself. For example, <code>info</code>, <code>macro</code>, +and <code>show</code> are in this category. Type <kbd>help status</kbd> at the +<small>GDB</small> prompt to see a list of commands in this category. +</p> +<a name="index-COMMAND_005fBREAKPOINTS"></a> +<a name="index-gdb_002eCOMMAND_005fBREAKPOINTS"></a> +</dd> +<dt><code>gdb.COMMAND_BREAKPOINTS</code></dt> +<dd><p>The command has to do with breakpoints. For example, <code>break</code>, +<code>clear</code>, and <code>delete</code> are in this category. Type <kbd>help +breakpoints</kbd> at the <small>GDB</small> prompt to see a list of commands in +this category. +</p> +<a name="index-COMMAND_005fTRACEPOINTS"></a> +<a name="index-gdb_002eCOMMAND_005fTRACEPOINTS"></a> +</dd> +<dt><code>gdb.COMMAND_TRACEPOINTS</code></dt> +<dd><p>The command has to do with tracepoints. For example, <code>trace</code>, +<code>actions</code>, and <code>tfind</code> are in this category. Type +<kbd>help tracepoints</kbd> at the <small>GDB</small> prompt to see a list of +commands in this category. +</p> +<a name="index-COMMAND_005fTUI"></a> +<a name="index-gdb_002eCOMMAND_005fTUI"></a> +</dd> +<dt><code>gdb.COMMAND_TUI</code></dt> +<dd><p>The command has to do with the text user interface (see <a href="TUI.html#TUI">TUI</a>). +Type <kbd>help tui</kbd> at the <small>GDB</small> prompt to see a list of +commands in this category. +</p> +<a name="index-COMMAND_005fUSER"></a> +<a name="index-gdb_002eCOMMAND_005fUSER"></a> +</dd> +<dt><code>gdb.COMMAND_USER</code></dt> +<dd><p>The command is a general purpose command for the user, and typically +does not fit in one of the other categories. +Type <kbd>help user-defined</kbd> at the <small>GDB</small> prompt to see +a list of commands in this category, as well as the list of gdb macros +(see <a href="Sequences.html#Sequences">Sequences</a>). +</p> +<a name="index-COMMAND_005fOBSCURE"></a> +<a name="index-gdb_002eCOMMAND_005fOBSCURE"></a> +</dd> +<dt><code>gdb.COMMAND_OBSCURE</code></dt> +<dd><p>The command is only used in unusual circumstances, or is not of +general interest to users. For example, <code>checkpoint</code>, +<code>fork</code>, and <code>stop</code> are in this category. Type <kbd>help +obscure</kbd> at the <small>GDB</small> prompt to see a list of commands in this +category. +</p> +<a name="index-COMMAND_005fMAINTENANCE"></a> +<a name="index-gdb_002eCOMMAND_005fMAINTENANCE"></a> +</dd> +<dt><code>gdb.COMMAND_MAINTENANCE</code></dt> +<dd><p>The command is only useful to <small>GDB</small> maintainers. The +<code>maintenance</code> and <code>flushregs</code> commands are in this category. +Type <kbd>help internals</kbd> at the <small>GDB</small> prompt to see a list of +commands in this category. +</p></dd> +</dl> + +<p>A new command can use a predefined completion function, either by +specifying it via an argument at initialization, or by returning it +from the <code>complete</code> method. These predefined completion +constants are all defined in the <code>gdb</code> module: +</p> +<dl compact="compact"> +<dd><a name="index-COMPLETE_005fNONE"></a> +</dd> +<dt><code>gdb.COMPLETE_NONE</code> +<a name="index-gdb_002eCOMPLETE_005fNONE"></a> +</dt> +<dd><p>This constant means that no completion should be done. +</p> +<a name="index-COMPLETE_005fFILENAME"></a> +</dd> +<dt><code>gdb.COMPLETE_FILENAME</code> +<a name="index-gdb_002eCOMPLETE_005fFILENAME"></a> +</dt> +<dd><p>This constant means that filename completion should be performed. +</p> +<a name="index-COMPLETE_005fLOCATION"></a> +</dd> +<dt><code>gdb.COMPLETE_LOCATION</code> +<a name="index-gdb_002eCOMPLETE_005fLOCATION"></a> +</dt> +<dd><p>This constant means that location completion should be done. +See <a href="Location-Specifications.html#Location-Specifications">Location Specifications</a>. +</p> +<a name="index-COMPLETE_005fCOMMAND"></a> +</dd> +<dt><code>gdb.COMPLETE_COMMAND</code> +<a name="index-gdb_002eCOMPLETE_005fCOMMAND"></a> +</dt> +<dd><p>This constant means that completion should examine <small>GDB</small> +command names. +</p> +<a name="index-COMPLETE_005fSYMBOL"></a> +</dd> +<dt><code>gdb.COMPLETE_SYMBOL</code> +<a name="index-gdb_002eCOMPLETE_005fSYMBOL"></a> +</dt> +<dd><p>This constant means that completion should be done using symbol names +as the source. +</p> +<a name="index-COMPLETE_005fEXPRESSION"></a> +</dd> +<dt><code>gdb.COMPLETE_EXPRESSION</code> +<a name="index-gdb_002eCOMPLETE_005fEXPRESSION"></a> +</dt> +<dd><p>This constant means that completion should be done on expressions. +Often this means completing on symbol names, but some language +parsers also have support for completing on field names. +</p></dd> +</dl> + +<p>The following code snippet shows how a trivial CLI command can be +implemented in Python: +</p> +<div class="smallexample"> +<pre class="smallexample">class HelloWorld (gdb.Command): + """Greet the whole world.""" + + def __init__ (self): + super (HelloWorld, self).__init__ ("hello-world", gdb.COMMAND_USER) + + def invoke (self, arg, from_tty): + print ("Hello, World!") + +HelloWorld () +</pre></div> + +<p>The last line instantiates the class, and is necessary to trigger the +registration of the command with <small>GDB</small>. Depending on how the +Python code is read into <small>GDB</small>, you may need to import the +<code>gdb</code> module explicitly. +</p> +<hr> +<div class="header"> +<p> +Next: <a href="GDB_002fMI-Commands-In-Python.html#GDB_002fMI-Commands-In-Python" accesskey="n" rel="next">GDB/MI Commands In Python</a>, Previous: <a href="Recordings-In-Python.html#Recordings-In-Python" accesskey="p" rel="previous">Recordings 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> +</div> + + + +</body> +</html> |