Edit File: pdb.html
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Debugging and Profiling</a> »</li> </ul> </div> <div class="document"> <div class="documentwrapper"> <div class="bodywrapper"> <div class="body"> <div class="section" id="module-pdb"> <span id="pdb-the-python-debugger"></span><span id="debugger"></span><h1>26.2. <a class="reference internal" href="#module-pdb" title="pdb: The Python debugger for interactive interpreters."><tt class="xref py py-mod docutils literal"><span class="pre">pdb</span></tt></a> — The Python Debugger<a class="headerlink" href="#module-pdb" title="Permalink to this headline">¶</a></h1> <p id="index-0">The module <a class="reference internal" href="#module-pdb" title="pdb: The Python debugger for interactive interpreters."><tt class="xref py py-mod docutils literal"><span class="pre">pdb</span></tt></a> defines an interactive source code debugger for Python programs. It supports setting (conditional) breakpoints and single stepping at the source line level, inspection of stack frames, source code listing, and evaluation of arbitrary Python code in the context of any stack frame. It also supports post-mortem debugging and can be called under program control.</p> <p id="index-1">The debugger is extensible — it is actually defined as the class <a class="reference internal" href="#pdb.Pdb" title="pdb.Pdb"><tt class="xref py py-class docutils literal"><span class="pre">Pdb</span></tt></a>. This is currently undocumented but easily understood by reading the source. The extension interface uses the modules <a class="reference internal" href="bdb.html#module-bdb" title="bdb: Debugger framework."><tt class="xref py py-mod docutils literal"><span class="pre">bdb</span></tt></a> and <a class="reference internal" href="cmd.html#module-cmd" title="cmd: Build line-oriented command interpreters."><tt class="xref py py-mod docutils literal"><span class="pre">cmd</span></tt></a>.</p> <p>The debugger’s prompt is <tt class="docutils literal"><span class="pre">(Pdb)</span></tt>. Typical usage to run a program under control of the debugger is:</p> <div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="kn">import</span> <span class="nn">pdb</span> <span class="gp">>>> </span><span class="kn">import</span> <span class="nn">mymodule</span> <span class="gp">>>> </span><span class="n">pdb</span><span class="o">.</span><span class="n">run</span><span class="p">(</span><span class="s">'mymodule.test()'</span><span class="p">)</span> <span class="go">> <string>(0)?()</span> <span class="go">(Pdb) continue</span> <span class="go">> <string>(1)?()</span> <span class="go">(Pdb) continue</span> <span class="go">NameError: 'spam'</span> <span class="go">> <string>(1)?()</span> <span class="go">(Pdb)</span> </pre></div> </div> <p><tt class="file docutils literal"><span class="pre">pdb.py</span></tt> can also be invoked as a script to debug other scripts. For example:</p> <div class="highlight-python"><pre>python -m pdb myscript.py</pre> </div> <p>When invoked as a script, pdb will automatically enter post-mortem debugging if the program being debugged exits abnormally. After post-mortem debugging (or after normal exit of the program), pdb will restart the program. Automatic restarting preserves pdb’s state (such as breakpoints) and in most cases is more useful than quitting the debugger upon program’s exit.</p> <p class="versionadded"> <span class="versionmodified">New in version 2.4: </span>Restarting post-mortem behavior added.</p> <p>The typical usage to break into the debugger from a running program is to insert</p> <div class="highlight-python"><div class="highlight"><pre><span class="kn">import</span> <span class="nn">pdb</span><span class="p">;</span> <span class="n">pdb</span><span class="o">.</span><span class="n">set_trace</span><span class="p">()</span> </pre></div> </div> <p>at the location you want to break into the debugger. You can then step through the code following this statement, and continue running without the debugger using the <tt class="docutils literal"><span class="pre">c</span></tt> command.</p> <p>The typical usage to inspect a crashed program is:</p> <div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="kn">import</span> <span class="nn">pdb</span> <span class="gp">>>> </span><span class="kn">import</span> <span class="nn">mymodule</span> <span class="gp">>>> </span><span class="n">mymodule</span><span class="o">.</span><span class="n">test</span><span class="p">()</span> <span class="gt">Traceback (most recent call last):</span> File <span class="nb">"<stdin>"</span>, line <span class="m">1</span>, in <span class="n">?</span> File <span class="nb">"./mymodule.py"</span>, line <span class="m">4</span>, in <span class="n">test</span> <span class="n">test2</span><span class="p">()</span> File <span class="nb">"./mymodule.py"</span>, line <span class="m">3</span>, in <span class="n">test2</span> <span class="k">print</span> <span class="n">spam</span> <span class="gr">NameError</span>: <span class="n">spam</span> <span class="gp">>>> </span><span class="n">pdb</span><span class="o">.</span><span class="n">pm</span><span class="p">()</span> <span class="go">> ./mymodule.py(3)test2()</span> <span class="go">-> print spam</span> <span class="go">(Pdb)</span> </pre></div> </div> <p>The module defines the following functions; each enters the debugger in a slightly different way:</p> <dl class="function"> <dt id="pdb.run"> <tt class="descclassname">pdb.</tt><tt class="descname">run</tt><big>(</big><em>statement</em><span class="optional">[</span>, <em>globals</em><span class="optional">[</span>, <em>locals</em><span class="optional">]</span><span class="optional">]</span><big>)</big><a class="headerlink" href="#pdb.run" title="Permalink to this definition">¶</a></dt> <dd><p>Execute the <em>statement</em> (given as a string) under debugger control. The debugger prompt appears before any code is executed; you can set breakpoints and type <tt class="docutils literal"><span class="pre">continue</span></tt>, or you can step through the statement using <tt class="docutils literal"><span class="pre">step</span></tt> or <tt class="docutils literal"><span class="pre">next</span></tt> (all these commands are explained below). The optional <em>globals</em> and <em>locals</em> arguments specify the environment in which the code is executed; by default the dictionary of the module <a class="reference internal" href="__main__.html#module-__main__" title="__main__: The environment where the top-level script is run."><tt class="xref py py-mod docutils literal"><span class="pre">__main__</span></tt></a> is used. (See the explanation of the <a class="reference internal" href="../reference/simple_stmts.html#exec"><tt class="xref std std-keyword docutils literal"><span class="pre">exec</span></tt></a> statement or the <a class="reference internal" href="functions.html#eval" title="eval"><tt class="xref py py-func docutils literal"><span class="pre">eval()</span></tt></a> built-in function.)</p> </dd></dl> <dl class="function"> <dt id="pdb.runeval"> <tt class="descclassname">pdb.</tt><tt class="descname">runeval</tt><big>(</big><em>expression</em><span class="optional">[</span>, <em>globals</em><span class="optional">[</span>, <em>locals</em><span class="optional">]</span><span class="optional">]</span><big>)</big><a class="headerlink" href="#pdb.runeval" title="Permalink to this definition">¶</a></dt> <dd><p>Evaluate the <em>expression</em> (given as a string) under debugger control. When <a class="reference internal" href="#pdb.runeval" title="pdb.runeval"><tt class="xref py py-func docutils literal"><span class="pre">runeval()</span></tt></a> returns, it returns the value of the expression. Otherwise this function is similar to <a class="reference internal" href="#pdb.run" title="pdb.run"><tt class="xref py py-func docutils literal"><span class="pre">run()</span></tt></a>.</p> </dd></dl> <dl class="function"> <dt id="pdb.runcall"> <tt class="descclassname">pdb.</tt><tt class="descname">runcall</tt><big>(</big><em>function</em><span class="optional">[</span>, <em>argument</em>, <em>...</em><span class="optional">]</span><big>)</big><a class="headerlink" href="#pdb.runcall" title="Permalink to this definition">¶</a></dt> <dd><p>Call the <em>function</em> (a function or method object, not a string) with the given arguments. When <a class="reference internal" href="#pdb.runcall" title="pdb.runcall"><tt class="xref py py-func docutils literal"><span class="pre">runcall()</span></tt></a> returns, it returns whatever the function call returned. The debugger prompt appears as soon as the function is entered.</p> </dd></dl> <dl class="function"> <dt id="pdb.set_trace"> <tt class="descclassname">pdb.</tt><tt class="descname">set_trace</tt><big>(</big><big>)</big><a class="headerlink" href="#pdb.set_trace" title="Permalink to this definition">¶</a></dt> <dd><p>Enter the debugger at the calling stack frame. This is useful to hard-code a breakpoint at a given point in a program, even if the code is not otherwise being debugged (e.g. when an assertion fails).</p> </dd></dl> <dl class="function"> <dt id="pdb.post_mortem"> <tt class="descclassname">pdb.</tt><tt class="descname">post_mortem</tt><big>(</big><span class="optional">[</span><em>traceback</em><span class="optional">]</span><big>)</big><a class="headerlink" href="#pdb.post_mortem" title="Permalink to this definition">¶</a></dt> <dd><p>Enter post-mortem debugging of the given <em>traceback</em> object. If no <em>traceback</em> is given, it uses the one of the exception that is currently being handled (an exception must be being handled if the default is to be used).</p> </dd></dl> <dl class="function"> <dt id="pdb.pm"> <tt class="descclassname">pdb.</tt><tt class="descname">pm</tt><big>(</big><big>)</big><a class="headerlink" href="#pdb.pm" title="Permalink to this definition">¶</a></dt> <dd><p>Enter post-mortem debugging of the traceback found in <a class="reference internal" href="sys.html#sys.last_traceback" title="sys.last_traceback"><tt class="xref py py-data docutils literal"><span class="pre">sys.last_traceback</span></tt></a>.</p> </dd></dl> <p>The <tt class="docutils literal"><span class="pre">run*</span></tt> functions and <a class="reference internal" href="#pdb.set_trace" title="pdb.set_trace"><tt class="xref py py-func docutils literal"><span class="pre">set_trace()</span></tt></a> are aliases for instantiating the <a class="reference internal" href="#pdb.Pdb" title="pdb.Pdb"><tt class="xref py py-class docutils literal"><span class="pre">Pdb</span></tt></a> class and calling the method of the same name. If you want to access further features, you have to do this yourself:</p> <dl class="class"> <dt id="pdb.Pdb"> <em class="property">class </em><tt class="descclassname">pdb.</tt><tt class="descname">Pdb</tt><big>(</big><em>completekey='tab'</em>, <em>stdin=None</em>, <em>stdout=None</em>, <em>skip=None</em><big>)</big><a class="headerlink" href="#pdb.Pdb" title="Permalink to this definition">¶</a></dt> <dd><p><a class="reference internal" href="#pdb.Pdb" title="pdb.Pdb"><tt class="xref py py-class docutils literal"><span class="pre">Pdb</span></tt></a> is the debugger class.</p> <p>The <em>completekey</em>, <em>stdin</em> and <em>stdout</em> arguments are passed to the underlying <a class="reference internal" href="cmd.html#cmd.Cmd" title="cmd.Cmd"><tt class="xref py py-class docutils literal"><span class="pre">cmd.Cmd</span></tt></a> class; see the description there.</p> <p>The <em>skip</em> argument, if given, must be an iterable of glob-style module name patterns. The debugger will not step into frames that originate in a module that matches one of these patterns. <a class="footnote-reference" href="#id3" id="id1">[1]</a></p> <p>Example call to enable tracing with <em>skip</em>:</p> <div class="highlight-python"><div class="highlight"><pre><span class="kn">import</span> <span class="nn">pdb</span><span class="p">;</span> <span class="n">pdb</span><span class="o">.</span><span class="n">Pdb</span><span class="p">(</span><span class="n">skip</span><span class="o">=</span><span class="p">[</span><span class="s">'django.*'</span><span class="p">])</span><span class="o">.</span><span class="n">set_trace</span><span class="p">()</span> </pre></div> </div> <p class="versionadded"> <span class="versionmodified">New in version 2.7: </span>The <em>skip</em> argument.</p> <dl class="method"> <dt id="pdb.Pdb.run"> <tt class="descname">run</tt><big>(</big><em>statement</em><span class="optional">[</span>, <em>globals</em><span class="optional">[</span>, <em>locals</em><span class="optional">]</span><span class="optional">]</span><big>)</big><a class="headerlink" href="#pdb.Pdb.run" title="Permalink to this definition">¶</a></dt> <dt id="pdb.Pdb.runeval"> <tt class="descname">runeval</tt><big>(</big><em>expression</em><span class="optional">[</span>, <em>globals</em><span class="optional">[</span>, <em>locals</em><span class="optional">]</span><span class="optional">]</span><big>)</big><a class="headerlink" href="#pdb.Pdb.runeval" title="Permalink to this definition">¶</a></dt> <dt id="pdb.Pdb.runcall"> <tt class="descname">runcall</tt><big>(</big><em>function</em><span class="optional">[</span>, <em>argument</em>, <em>...</em><span class="optional">]</span><big>)</big><a class="headerlink" href="#pdb.Pdb.runcall" title="Permalink to this definition">¶</a></dt> <dt id="pdb.Pdb.set_trace"> <tt class="descname">set_trace</tt><big>(</big><big>)</big><a class="headerlink" href="#pdb.Pdb.set_trace" title="Permalink to this definition">¶</a></dt> <dd><p>See the documentation for the functions explained above.</p> </dd></dl> </dd></dl> </div> <div class="section" id="debugger-commands"> <span id="id2"></span><h1>26.3. Debugger Commands<a class="headerlink" href="#debugger-commands" title="Permalink to this headline">¶</a></h1> <p>The debugger recognizes the following commands. Most commands can be abbreviated to one or two letters; e.g. <tt class="docutils literal"><span class="pre">h(elp)</span></tt> means that either <tt class="docutils literal"><span class="pre">h</span></tt> or <tt class="docutils literal"><span class="pre">help</span></tt> can be used to enter the help command (but not <tt class="docutils literal"><span class="pre">he</span></tt> or <tt class="docutils literal"><span class="pre">hel</span></tt>, nor <tt class="docutils literal"><span class="pre">H</span></tt> or <tt class="docutils literal"><span class="pre">Help</span></tt> or <tt class="docutils literal"><span class="pre">HELP</span></tt>). Arguments to commands must be separated by whitespace (spaces or tabs). Optional arguments are enclosed in square brackets (<tt class="docutils literal"><span class="pre">[]</span></tt>) in the command syntax; the square brackets must not be typed. Alternatives in the command syntax are separated by a vertical bar (<tt class="docutils literal"><span class="pre">|</span></tt>).</p> <p>Entering a blank line repeats the last command entered. Exception: if the last command was a <tt class="docutils literal"><span class="pre">list</span></tt> command, the next 11 lines are listed.</p> <p>Commands that the debugger doesn’t recognize are assumed to be Python statements and are executed in the context of the program being debugged. Python statements can also be prefixed with an exclamation point (<tt class="docutils literal"><span class="pre">!</span></tt>). This is a powerful way to inspect the program being debugged; it is even possible to change a variable or call a function. When an exception occurs in such a statement, the exception name is printed but the debugger’s state is not changed.</p> <p>Multiple commands may be entered on a single line, separated by <tt class="docutils literal"><span class="pre">;;</span></tt>. (A single <tt class="docutils literal"><span class="pre">;</span></tt> is not used as it is the separator for multiple commands in a line that is passed to the Python parser.) No intelligence is applied to separating the commands; the input is split at the first <tt class="docutils literal"><span class="pre">;;</span></tt> pair, even if it is in the middle of a quoted string.</p> <p>The debugger supports aliases. Aliases can have parameters which allows one a certain level of adaptability to the context under examination.</p> <p id="index-2">If a file <tt class="file docutils literal"><span class="pre">.pdbrc</span></tt> exists in the user’s home directory or in the current directory, it is read in and executed as if it had been typed at the debugger prompt. This is particularly useful for aliases. If both files exist, the one in the home directory is read first and aliases defined there can be overridden by the local file.</p> <dl class="docutils"> <dt>h(elp) [<em>command</em>]</dt> <dd>Without argument, print the list of available commands. With a <em>command</em> as argument, print help about that command. <tt class="docutils literal"><span class="pre">help</span> <span class="pre">pdb</span></tt> displays the full documentation file; if the environment variable <span class="target" id="index-3"></span><tt class="xref std std-envvar docutils literal"><span class="pre">PAGER</span></tt> is defined, the file is piped through that command instead. Since the <em>command</em> argument must be an identifier, <tt class="docutils literal"><span class="pre">help</span> <span class="pre">exec</span></tt> must be entered to get help on the <tt class="docutils literal"><span class="pre">!</span></tt> command.</dd> <dt>w(here)</dt> <dd>Print a stack trace, with the most recent frame at the bottom. An arrow indicates the current frame, which determines the context of most commands.</dd> <dt>d(own)</dt> <dd>Move the current frame one level down in the stack trace (to a newer frame).</dd> <dt>u(p)</dt> <dd>Move the current frame one level up in the stack trace (to an older frame).</dd> <dt>b(reak) [[<em>filename</em>:]<em>lineno</em> | <em>function</em>[, <em>condition</em>]]</dt> <dd><p class="first">With a <em>lineno</em> argument, set a break there in the current file. With a <em>function</em> argument, set a break at the first executable statement within that function. The line number may be prefixed with a filename and a colon, to specify a breakpoint in another file (probably one that hasn’t been loaded yet). The file is searched on <tt class="docutils literal"><span class="pre">sys.path</span></tt>. Note that each breakpoint is assigned a number to which all the other breakpoint commands refer.</p> <p>If a second argument is present, it is an expression which must evaluate to true before the breakpoint is honored.</p> <p class="last">Without argument, list all breaks, including for each breakpoint, the number of times that breakpoint has been hit, the current ignore count, and the associated condition if any.</p> </dd> <dt>tbreak [[<em>filename</em>:]<em>lineno</em> | <em>function</em>[, <em>condition</em>]]</dt> <dd>Temporary breakpoint, which is removed automatically when it is first hit. The arguments are the same as break.</dd> <dt>cl(ear) [<em>filename:lineno</em> | <em>bpnumber</em> [<em>bpnumber ...</em>]]</dt> <dd>With a <em>filename:lineno</em> argument, clear all the breakpoints at this line. With a space separated list of breakpoint numbers, clear those breakpoints. Without argument, clear all breaks (but first ask confirmation).</dd> <dt>disable [<em>bpnumber</em> [<em>bpnumber ...</em>]]</dt> <dd>Disables the breakpoints given as a space separated list of breakpoint numbers. Disabling a breakpoint means it cannot cause the program to stop execution, but unlike clearing a breakpoint, it remains in the list of breakpoints and can be (re-)enabled.</dd> <dt>enable [<em>bpnumber</em> [<em>bpnumber ...</em>]]</dt> <dd>Enables the breakpoints specified.</dd> <dt>ignore <em>bpnumber</em> [<em>count</em>]</dt> <dd>Sets the ignore count for the given breakpoint number. If count is omitted, the ignore count is set to 0. A breakpoint becomes active when the ignore count is zero. When non-zero, the count is decremented each time the breakpoint is reached and the breakpoint is not disabled and any associated condition evaluates to true.</dd> <dt>condition <em>bpnumber</em> [<em>condition</em>]</dt> <dd>Condition is an expression which must evaluate to true before the breakpoint is honored. If condition is absent, any existing condition is removed; i.e., the breakpoint is made unconditional.</dd> <dt>commands [<em>bpnumber</em>]</dt> <dd><p class="first">Specify a list of commands for breakpoint number <em>bpnumber</em>. The commands themselves appear on the following lines. Type a line containing just ‘end’ to terminate the commands. An example:</p> <div class="highlight-python"><pre>(Pdb) commands 1 (com) print some_variable (com) end (Pdb)</pre> </div> <p>To remove all commands from a breakpoint, type commands and follow it immediately with end; that is, give no commands.</p> <p>With no <em>bpnumber</em> argument, commands refers to the last breakpoint set.</p> <p>You can use breakpoint commands to start your program up again. Simply use the continue command, or step, or any other command that resumes execution.</p> <p>Specifying any command resuming execution (currently continue, step, next, return, jump, quit and their abbreviations) terminates the command list (as if that command was immediately followed by end). This is because any time you resume execution (even with a simple next or step), you may encounter another breakpoint–which could have its own command list, leading to ambiguities about which list to execute.</p> <p>If you use the ‘silent’ command in the command list, the usual message about stopping at a breakpoint is not printed. This may be desirable for breakpoints that are to print a specific message and then continue. If none of the other commands print anything, you see no sign that the breakpoint was reached.</p> <p class="last versionadded"> <span class="versionmodified">New in version 2.5.</span></p> </dd> <dt>s(tep)</dt> <dd>Execute the current line, stop at the first possible occasion (either in a function that is called or on the next line in the current function).</dd> <dt>n(ext)</dt> <dd>Continue execution until the next line in the current function is reached or it returns. (The difference between <tt class="docutils literal"><span class="pre">next</span></tt> and <tt class="docutils literal"><span class="pre">step</span></tt> is that <tt class="docutils literal"><span class="pre">step</span></tt> stops inside a called function, while <tt class="docutils literal"><span class="pre">next</span></tt> executes called functions at (nearly) full speed, only stopping at the next line in the current function.)</dd> <dt>unt(il)</dt> <dd><p class="first">Continue execution until the line with the line number greater than the current one is reached or when returning from current frame.</p> <p class="last versionadded"> <span class="versionmodified">New in version 2.6.</span></p> </dd> <dt>r(eturn)</dt> <dd>Continue execution until the current function returns.</dd> <dt>c(ont(inue))</dt> <dd>Continue execution, only stop when a breakpoint is encountered.</dd> <dt>j(ump) <em>lineno</em></dt> <dd><p class="first">Set the next line that will be executed. Only available in the bottom-most frame. This lets you jump back and execute code again, or jump forward to skip code that you don’t want to run.</p> <p class="last">It should be noted that not all jumps are allowed — for instance it is not possible to jump into the middle of a <a class="reference internal" href="../reference/compound_stmts.html#for"><tt class="xref std std-keyword docutils literal"><span class="pre">for</span></tt></a> loop or out of a <a class="reference internal" href="../reference/compound_stmts.html#finally"><tt class="xref std std-keyword docutils literal"><span class="pre">finally</span></tt></a> clause.</p> </dd> <dt>l(ist) [<em>first</em>[, <em>last</em>]]</dt> <dd>List source code for the current file. Without arguments, list 11 lines around the current line or continue the previous listing. With one argument, list 11 lines around at that line. With two arguments, list the given range; if the second argument is less than the first, it is interpreted as a count.</dd> <dt>a(rgs)</dt> <dd>Print the argument list of the current function.</dd> <dt>p <em>expression</em></dt> <dd><p class="first">Evaluate the <em>expression</em> in the current context and print its value.</p> <div class="last admonition note"> <p class="first admonition-title">Note</p> <p class="last"><tt class="docutils literal"><span class="pre">print</span></tt> can also be used, but is not a debugger command — this executes the Python <a class="reference internal" href="../reference/simple_stmts.html#print"><tt class="xref std std-keyword docutils literal"><span class="pre">print</span></tt></a> statement.</p> </div> </dd> <dt>pp <em>expression</em></dt> <dd>Like the <tt class="docutils literal"><span class="pre">p</span></tt> command, except the value of the expression is pretty-printed using the <a class="reference internal" href="pprint.html#module-pprint" title="pprint: Data pretty printer."><tt class="xref py py-mod docutils literal"><span class="pre">pprint</span></tt></a> module.</dd> <dt>alias [<em>name</em> [command]]</dt> <dd><p class="first">Creates an alias called <em>name</em> that executes <em>command</em>. The command must <em>not</em> be enclosed in quotes. Replaceable parameters can be indicated by <tt class="docutils literal"><span class="pre">%1</span></tt>, <tt class="docutils literal"><span class="pre">%2</span></tt>, and so on, while <tt class="docutils literal"><span class="pre">%*</span></tt> is replaced by all the parameters. If no command is given, the current alias for <em>name</em> is shown. If no arguments are given, all aliases are listed.</p> <p>Aliases may be nested and can contain anything that can be legally typed at the pdb prompt. Note that internal pdb commands <em>can</em> be overridden by aliases. Such a command is then hidden until the alias is removed. Aliasing is recursively applied to the first word of the command line; all other words in the line are left alone.</p> <p>As an example, here are two useful aliases (especially when placed in the <tt class="file docutils literal"><span class="pre">.pdbrc</span></tt> file):</p> <div class="last highlight-python"><pre>#Print instance variables (usage "pi classInst") alias pi for k in %1.__dict__.keys(): print "%1.",k,"=",%1.__dict__[k] #Print instance variables in self alias ps pi self</pre> </div> </dd> <dt>unalias <em>name</em></dt> <dd>Deletes the specified alias.</dd> <dt>[!]<em>statement</em></dt> <dd><p class="first">Execute the (one-line) <em>statement</em> in the context of the current stack frame. The exclamation point can be omitted unless the first word of the statement resembles a debugger command. To set a global variable, you can prefix the assignment command with a <tt class="docutils literal"><span class="pre">global</span></tt> command on the same line, e.g.:</p> <div class="last highlight-python"><pre>(Pdb) global list_options; list_options = ['-l'] (Pdb)</pre> </div> </dd> <dt>run [<em>args</em> ...]</dt> <dd><p class="first">Restart the debugged Python program. If an argument is supplied, it is split with “shlex” and the result is used as the new sys.argv. History, breakpoints, actions and debugger options are preserved. “restart” is an alias for “run”.</p> <p class="last versionadded"> <span class="versionmodified">New in version 2.6.</span></p> </dd> <dt>q(uit)</dt> <dd>Quit from the debugger. The program being executed is aborted.</dd> </dl> <p class="rubric">Footnotes</p> <table class="docutils footnote" frame="void" id="id3" rules="none"> <colgroup><col class="label" /><col /></colgroup> <tbody valign="top"> <tr><td class="label"><a class="fn-backref" href="#id1">[1]</a></td><td>Whether a frame is considered to originate in a certain module is determined by the <tt class="docutils literal"><span class="pre">__name__</span></tt> in the frame globals.</td></tr> </tbody> </table> </div> </div> </div> </div> <div class="sphinxsidebar"> <div class="sphinxsidebarwrapper"> <h3><a href="../contents.html">Table Of Contents</a></h3> <ul> <li><a class="reference internal" href="#">26.2. <tt class="docutils literal"><span class="pre">pdb</span></tt> — The Python Debugger</a></li> <li><a class="reference internal" href="#debugger-commands">26.3. Debugger Commands</a></li> </ul> <h4>Previous topic</h4> <p class="topless"><a href="bdb.html" title="previous chapter">26.1. <tt class="docutils literal"><span class="pre">bdb</span></tt> — Debugger framework</a></p> <h4>Next topic</h4> <p class="topless"><a href="profile.html" title="next chapter">26.4. The Python Profilers</a></p> <h3>This Page</h3> <ul class="this-page-menu"> <li><a href="../bugs.html">Report a Bug</a></li> <li><a href="../_sources/library/pdb.txt" rel="nofollow">Show Source</a></li> </ul> <div id="searchbox" style="display: none"> <h3>Quick search</h3> <form class="search" action="../search.html" method="get"> <input type="text" name="q" /> <input type="submit" value="Go" /> <input type="hidden" name="check_keywords" value="yes" /> <input type="hidden" name="area" value="default" /> </form> <p class="searchtip" style="font-size: 90%"> Enter search terms or a module, class or function name. </p> </div> <script type="text/javascript">$('#searchbox').show(0);</script> </div> </div> <div class="clearer"></div> </div> <div class="related"> <h3>Navigation</h3> <ul> <li class="right" style="margin-right: 10px"> <a href="../genindex.html" title="General Index" >index</a></li> <li class="right" > <a href="../py-modindex.html" title="Python Module Index" >modules</a> |</li> <li class="right" > <a href="profile.html" title="26.4. 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