ch06_02.htm

by Randal L. Schwartz and Tom Phoenix ISBN 0-596-00132-0 Third Edition, published July 2001. (See

Prints only to depth <em class="emphasis">n</em>
("" for all).
</p>
</dd>


<dt><b><tt class="literal">compactDump</tt>, <tt class="literal">veryCompact</tt></b></dt>
<dd>
Changes style of array and hash dumps.</p>
</dd>


<dt><b><tt class="literal">DumpDBFiles</tt></b></dt>
<dd>
Dumps arrays holding debugged files.</p>
</dd>


<dt><b><tt class="literal">DumpPackages</tt></b></dt>
<dd>
Dumps symbol tables of packages.</p>
</dd>


<dt><b><tt class="literal">globPrint</tt></b></dt>
<dd>
Specifies whether to print contents of globs.</p>
</dd>


<dt><b><tt class="literal">quote</tt>, <tt class="literal">HighBit</tt>, <tt class="literal">undefPrint</tt></b></dt>
<dd>
Changes style of string dump.</p>
</dd>


<dt><b><tt class="literal">signalLevel</tt>, <tt class="literal">warnLevel</tt>, <tt class="literal">dieLevel</tt></b></dt>
<dd>
Specifies level of verbosity.</p>
</dd>


<dt><b><tt class="literal">tkRunning</tt></b></dt>
<dd>
Runs Tk while prompting (with ReadLine).</p>
</dd>

</dl><p>During startup, debugger options are initialized from
<tt class="literal">$ENV{PERLDB_OPTS}</tt>. You can set the additional
initialization options <tt class="literal">TTY</tt>,
<tt class="literal">noTTY</tt>, <tt class="literal">ReadLine</tt>, and
<tt class="literal">NonStop</tt> there. See <a href="ch06_04.htm#perlnut2-CHP-6-SECT-4">Section 6.4, "Customizing the Debugger"</a> later in this chapter for
more information.
</p></div>

<a name="INDEX-1157" /><div class="refentry"><table width="515" border="0" cellpadding="5"><tr><td align="left"><font size="+1"><b>p</b</font></td><td align="right"><i></i></td></tr></table><hr width="515" size="3" noshade="true" align="left" color="black" /><pre>
p <em class="emphasis">expr</em>
</pre><p><a name="INDEX-1157" />Same as <tt class="literal">print
DB::OUT</tt> <em class="replaceable"><tt>expr</tt></em> in the current
package. In particular, does not dump nested data structures and
objects, unlike the <tt class="literal">x</tt> command. The DB::OUT handle
is opened to <em class="emphasis">/dev/tty</em> (or perhaps an editor
window) no matter where standard output may have been redirected to.
</p></div>

<a name="INDEX-1158" /><div class="refentry"><table width="515" border="0" cellpadding="5"><tr><td align="left"><font size="+1"><b>q</b</font></td><td align="right"><i></i></td></tr></table><hr width="515" size="3" noshade="true" align="left" color="black" /><pre>
q <em class="emphasis">or</em> ^D
</pre><p><a name="INDEX-1158" />Quits the debugger.
</p></div>

<a name="INDEX-1159" /><div class="refentry"><table width="515" border="0" cellpadding="5"><tr><td align="left"><font size="+1"><b>R</b</font></td><td align="right"><i></i></td></tr></table><hr width="515" size="3" noshade="true" align="left" color="black" /><pre>
R
</pre><p><a name="INDEX-1159" />Restarts the debugger. As much of your
history is maintained across the sessions as possible, but some
internal settings and command-line options may be lost.
</p></div>

<a name="INDEX-1160" /><div class="refentry"><table width="515" border="0" cellpadding="5"><tr><td align="left"><font size="+1"><b>r</b</font></td><td align="right"><i></i></td></tr></table><hr width="515" size="3" noshade="true" align="left" color="black" /><pre>
r
</pre><p><a name="INDEX-1160" />Returns from current subroutine.
</p></div>

<a name="INDEX-1161" /><div class="refentry"><table width="515" border="0" cellpadding="5"><tr><td align="left"><font size="+1"><b>S</b</font></td><td align="right"><i></i></td></tr></table><hr width="515" size="3" noshade="true" align="left" color="black" /><pre>
S [[!]<em class="emphasis">pattern</em>]
</pre><p><a name="INDEX-1161" />Lists subroutine names matching (or,
if <tt class="literal">!</tt> is specified, not matching)
<em class="replaceable"><tt>pattern</tt></em>. If
<em class="replaceable"><tt>pattern</tt></em> is omitted, lists all subroutines.
</p></div>

<a name="INDEX-1162" /><div class="refentry"><table width="515" border="0" cellpadding="5"><tr><td align="left"><font size="+1"><b>s</b</font></td><td align="right"><i></i></td></tr></table><hr width="515" size="3" noshade="true" align="left" color="black" /><pre>
s [<em class="emphasis">expr</em>]
</pre><p><a name="INDEX-1162" />Single steps. Executes until it
reaches the beginning of another statement, descending into
subroutine calls. If an expression is supplied that includes a
function call, the function is also single-stepped.
</p></div>

<a name="INDEX-1163" /><div class="refentry"><table width="515" border="0" cellpadding="5"><tr><td align="left"><font size="+1"><b>T</b</font></td><td align="right"><i></i></td></tr></table><hr width="515" size="3" noshade="true" align="left" color="black" /><pre>
T
</pre><p><a name="INDEX-1163" />Produces a stack backtrace. For
example:
</p><blockquote><pre class="code">DB&lt;2&gt; T
$ = main::infested called from file 'Ambulation.pm' line 10
@ = Ambulation::legs(1, 2, 3, 4) called from file 
'camel_flea' line 7
$ = main::pests('bactrian', 4) called from file 
'camel_flea' line 4</pre></blockquote><p>The lefthand character (<tt class="literal">$</tt> or <tt class="literal">@</tt>)
tells whether the function was called in a scalar or list context.
The example shows three lines because it was three functions deep
when the stack backtrace ran.
</p></div>

<a name="INDEX-1164" /><div class="refentry"><table width="515" border="0" cellpadding="5"><tr><td align="left"><font size="+1"><b>t</b</font></td><td align="right"><i></i></td></tr></table><hr width="515" size="3" noshade="true" align="left" color="black" /><pre>
t
</pre><p><a name="INDEX-1164" />Toggles trace mode.
</p></div>

<div class="refentry"><table width="515" border="0" cellpadding="5"><tr><td align="left"><font size="+1"><b>t</b</font></td><td align="right"><i></i></td></tr></table><hr width="515" size="3" noshade="true" align="left" color="black" /><pre>
t <em class="emphasis">expr</em>
</pre><p>Traces through execution of <em class="replaceable">expr</em>.</p></div>

<a name="INDEX-1165" /><div class="refentry"><table width="515" border="0" cellpadding="5"><tr><td align="left"><font size="+1"><b>v</b</font></td><td align="right"><i></i></td></tr></table><hr width="515" size="3" noshade="true" align="left" color="black" /><pre>
v
</pre><p><a name="INDEX-1165" />Shows versions of loaded modules.
</p></div>

<a name="INDEX-1166" /><div class="refentry"><table width="515" border="0" cellpadding="5"><tr><td align="left"><font size="+1"><b>V</b</font></td><td align="right"><i></i></td></tr></table><hr width="515" size="3" noshade="true" align="left" color="black" /><pre>
V [<em class="replaceable">pkg</em> [<em class="emphasis">vars</em>]]
</pre><p><a name="INDEX-1166" />Displays all (or some) variables in
package <em class="replaceable"><tt>pkg</tt></em> using a data pretty-printer
(which displays keys and their values for hashes, makes control
characters printable, prints nested data structures in a legible
fashion, and so on). <em class="replaceable"><tt>pkg</tt></em> defaults to the
<tt class="literal">main</tt> package. Make sure you enter the identifiers
without a type specifier such as <tt class="literal">$</tt> or
<tt class="literal">@</tt>, like this:
</p><blockquote><pre class="code">V DB filename line</pre></blockquote><p>In place of a variable name, you can use
<tt class="literal">~</tt><em class="emphasis">pattern</em> or
<tt class="literal">!</tt><em class="emphasis">pattern</em> to print existing
variables with names that either match or don't
match the specified regular expression.
</p></div>

<a name="INDEX-1167" /><div class="refentry"><table width="515" border="0" cellpadding="5"><tr><td align="left"><font size="+1"><b>w</b</font></td><td align="right"><i></i></td></tr></table><hr width="515" size="3" noshade="true" align="left" color="black" /><pre>
w [<em class="emphasis">line</em>]
</pre><p><a name="INDEX-1167" />Lists a window of a few lines around
the given <em class="replaceable"><tt>line</tt></em>, or lists the current line
if <em class="replaceable"><tt>line</tt></em> is omitted.
</p></div>

<a name="INDEX-1168" /><div class="refentry"><table width="515" border="0" cellpadding="5"><tr><td align="left"><font size="+1"><b>X</b</font></td><td align="right"><i></i></td></tr></table><hr width="515" size="3" noshade="true" align="left" color="black" /><pre>
X [<em class="emphasis">vars</em>]
</pre><p><a name="INDEX-1168" />Same as <tt class="literal">V</tt>
<em class="replaceable"><tt>currentpackage</em>[<em class="replaceable">vars</tt></em>].
</p></div>

<a name="INDEX-1169" /><div class="refentry"><table width="515" border="0" cellpadding="5"><tr><td align="left"><font size="+1"><b>x</b</font></td><td align="right"><i></i></td></tr></table><hr width="515" size="3" noshade="true" align="left" color="black" /><pre>
x <em class="emphasis">expr</em>
</pre><p><a name="INDEX-1169" /><tt class="literal">eval</tt>s the
expression in a list context and dumps out the result in a
pretty-printed fashion. Unlike the <tt class="literal">print</tt> command
above, prints nested data structures recursively.
</p></div>


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