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718 lines
28 KiB
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<head>
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<title>Print Settings (Debugging with GDB)</title>
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<meta name="description" content="Print Settings (Debugging with GDB)">
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<meta name="keywords" content="Print Settings (Debugging with GDB)">
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<link href="Concept-Index.html#Concept-Index" rel="index" title="Concept Index">
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<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
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<link href="Data.html#Data" rel="up" title="Data">
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<link href="Pretty-Printing.html#Pretty-Printing" rel="next" title="Pretty Printing">
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</head>
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<body lang="en">
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<a name="Print-Settings"></a>
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<div class="header">
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<p>
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Next: <a href="Pretty-Printing.html#Pretty-Printing" accesskey="n" rel="next">Pretty Printing</a>, Previous: <a href="Auto-Display.html#Auto-Display" accesskey="p" rel="prev">Auto Display</a>, Up: <a href="Data.html#Data" accesskey="u" rel="up">Data</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>
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</div>
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<hr>
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<a name="Print-Settings-1"></a>
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<h3 class="section">10.8 Print Settings</h3>
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<a name="index-format-options"></a>
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<a name="index-print-settings"></a>
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<p><small>GDB</small> provides the following ways to control how arrays, structures,
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and symbols are printed.
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</p>
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<p>These settings are useful for debugging programs in any language:
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</p>
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<dl compact="compact">
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<dd><a name="index-set-print"></a>
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</dd>
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<dt><code>set print address</code></dt>
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<dt><code>set print address on</code></dt>
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<dd><a name="index-print_002fdon_0027t-print-memory-addresses"></a>
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<p><small>GDB</small> prints memory addresses showing the location of stack
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traces, structure values, pointer values, breakpoints, and so forth,
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even when it also displays the contents of those addresses. The default
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is <code>on</code>. For example, this is what a stack frame display looks like with
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<code>set print address on</code>:
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</p>
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<div class="smallexample">
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<pre class="smallexample">(gdb) f
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#0 set_quotes (lq=0x34c78 "<<", rq=0x34c88 ">>")
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at input.c:530
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530 if (lquote != def_lquote)
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</pre></div>
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</dd>
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<dt><code>set print address off</code></dt>
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<dd><p>Do not print addresses when displaying their contents. For example,
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this is the same stack frame displayed with <code>set print address off</code>:
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</p>
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<div class="smallexample">
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<pre class="smallexample">(gdb) set print addr off
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(gdb) f
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#0 set_quotes (lq="<<", rq=">>") at input.c:530
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530 if (lquote != def_lquote)
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</pre></div>
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<p>You can use ‘<samp>set print address off</samp>’ to eliminate all machine
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dependent displays from the <small>GDB</small> interface. For example, with
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<code>print address off</code>, you should get the same text for backtraces on
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all machines—whether or not they involve pointer arguments.
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</p>
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<a name="index-show-print"></a>
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</dd>
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<dt><code>show print address</code></dt>
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<dd><p>Show whether or not addresses are to be printed.
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</p></dd>
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</dl>
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<p>When <small>GDB</small> prints a symbolic address, it normally prints the
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closest earlier symbol plus an offset. If that symbol does not uniquely
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identify the address (for example, it is a name whose scope is a single
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source file), you may need to clarify. One way to do this is with
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<code>info line</code>, for example ‘<samp>info line *0x4537</samp>’. Alternately,
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you can set <small>GDB</small> to print the source file and line number when
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it prints a symbolic address:
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</p>
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<dl compact="compact">
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<dt><code>set print symbol-filename on</code></dt>
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<dd><a name="index-source-file-and-line-of-a-symbol"></a>
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<a name="index-symbol_002c-source-file-and-line"></a>
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<p>Tell <small>GDB</small> to print the source file name and line number of a
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symbol in the symbolic form of an address.
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</p>
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</dd>
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<dt><code>set print symbol-filename off</code></dt>
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<dd><p>Do not print source file name and line number of a symbol. This is the
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default.
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</p>
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</dd>
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<dt><code>show print symbol-filename</code></dt>
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<dd><p>Show whether or not <small>GDB</small> will print the source file name and
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line number of a symbol in the symbolic form of an address.
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</p></dd>
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</dl>
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<p>Another situation where it is helpful to show symbol filenames and line
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numbers is when disassembling code; <small>GDB</small> shows you the line
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number and source file that corresponds to each instruction.
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</p>
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<p>Also, you may wish to see the symbolic form only if the address being
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printed is reasonably close to the closest earlier symbol:
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</p>
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<dl compact="compact">
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<dt><code>set print max-symbolic-offset <var>max-offset</var></code></dt>
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<dt><code>set print max-symbolic-offset unlimited</code></dt>
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<dd><a name="index-maximum-value-for-offset-of-closest-symbol"></a>
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<p>Tell <small>GDB</small> to only display the symbolic form of an address if the
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offset between the closest earlier symbol and the address is less than
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<var>max-offset</var>. The default is <code>unlimited</code>, which tells <small>GDB</small>
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to always print the symbolic form of an address if any symbol precedes
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it. Zero is equivalent to <code>unlimited</code>.
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</p>
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</dd>
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<dt><code>show print max-symbolic-offset</code></dt>
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<dd><p>Ask how large the maximum offset is that <small>GDB</small> prints in a
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symbolic address.
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</p></dd>
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</dl>
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<a name="index-wild-pointer_002c-interpreting"></a>
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<a name="index-pointer_002c-finding-referent"></a>
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<p>If you have a pointer and you are not sure where it points, try
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‘<samp>set print symbol-filename on</samp>’. Then you can determine the name
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and source file location of the variable where it points, using
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‘<samp>p/a <var>pointer</var></samp>’. This interprets the address in symbolic form.
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For example, here <small>GDB</small> shows that a variable <code>ptt</code> points
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at another variable <code>t</code>, defined in <samp>hi2.c</samp>:
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</p>
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<div class="smallexample">
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<pre class="smallexample">(gdb) set print symbol-filename on
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(gdb) p/a ptt
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$4 = 0xe008 <t in hi2.c>
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</pre></div>
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<blockquote>
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<p><em>Warning:</em> For pointers that point to a local variable, ‘<samp>p/a</samp>’
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does not show the symbol name and filename of the referent, even with
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the appropriate <code>set print</code> options turned on.
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</p></blockquote>
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<p>You can also enable ‘<samp>/a</samp>’-like formatting all the time using
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‘<samp>set print symbol on</samp>’:
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</p>
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<dl compact="compact">
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<dt><code>set print symbol on</code></dt>
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<dd><p>Tell <small>GDB</small> to print the symbol corresponding to an address, if
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one exists.
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</p>
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</dd>
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<dt><code>set print symbol off</code></dt>
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<dd><p>Tell <small>GDB</small> not to print the symbol corresponding to an
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address. In this mode, <small>GDB</small> will still print the symbol
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corresponding to pointers to functions. This is the default.
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</p>
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</dd>
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<dt><code>show print symbol</code></dt>
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<dd><p>Show whether <small>GDB</small> will display the symbol corresponding to an
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address.
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</p></dd>
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</dl>
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<p>Other settings control how different kinds of objects are printed:
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</p>
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<dl compact="compact">
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<dt><code>set print array</code></dt>
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<dt><code>set print array on</code></dt>
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<dd><a name="index-pretty-print-arrays"></a>
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<p>Pretty print arrays. This format is more convenient to read,
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but uses more space. The default is off.
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</p>
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</dd>
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<dt><code>set print array off</code></dt>
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<dd><p>Return to compressed format for arrays.
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</p>
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</dd>
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<dt><code>show print array</code></dt>
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<dd><p>Show whether compressed or pretty format is selected for displaying
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arrays.
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</p>
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<a name="index-print-array-indexes"></a>
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</dd>
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<dt><code>set print array-indexes</code></dt>
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<dt><code>set print array-indexes on</code></dt>
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<dd><p>Print the index of each element when displaying arrays. May be more
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convenient to locate a given element in the array or quickly find the
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index of a given element in that printed array. The default is off.
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</p>
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</dd>
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<dt><code>set print array-indexes off</code></dt>
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<dd><p>Stop printing element indexes when displaying arrays.
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</p>
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</dd>
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<dt><code>show print array-indexes</code></dt>
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<dd><p>Show whether the index of each element is printed when displaying
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arrays.
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</p>
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</dd>
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<dt><code>set print elements <var>number-of-elements</var></code></dt>
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<dt><code>set print elements unlimited</code></dt>
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<dd><a name="index-number-of-array-elements-to-print"></a>
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<a name="index-limit-on-number-of-printed-array-elements"></a>
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<p>Set a limit on how many elements of an array <small>GDB</small> will print.
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If <small>GDB</small> is printing a large array, it stops printing after it has
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printed the number of elements set by the <code>set print elements</code> command.
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This limit also applies to the display of strings.
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When <small>GDB</small> starts, this limit is set to 200.
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Setting <var>number-of-elements</var> to <code>unlimited</code> or zero means
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that the number of elements to print is unlimited.
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</p>
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</dd>
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<dt><code>show print elements</code></dt>
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<dd><p>Display the number of elements of a large array that <small>GDB</small> will print.
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If the number is 0, then the printing is unlimited.
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</p>
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</dd>
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<dt><code>set print frame-arguments <var>value</var></code></dt>
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<dd><a name="index-set-print-frame_002darguments"></a>
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<a name="index-printing-frame-argument-values"></a>
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<a name="index-print-all-frame-argument-values"></a>
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<a name="index-print-frame-argument-values-for-scalars-only"></a>
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<a name="index-do-not-print-frame-argument-values"></a>
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<p>This command allows to control how the values of arguments are printed
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when the debugger prints a frame (see <a href="Frames.html#Frames">Frames</a>). The possible
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values are:
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</p>
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<dl compact="compact">
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<dt><code>all</code></dt>
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<dd><p>The values of all arguments are printed.
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</p>
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</dd>
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<dt><code>scalars</code></dt>
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<dd><p>Print the value of an argument only if it is a scalar. The value of more
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complex arguments such as arrays, structures, unions, etc, is replaced
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by <code>…</code>. This is the default. Here is an example where
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only scalar arguments are shown:
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</p>
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<div class="smallexample">
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<pre class="smallexample">#1 0x08048361 in call_me (i=3, s=…, ss=0xbf8d508c, u=…, e=green)
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at frame-args.c:23
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</pre></div>
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</dd>
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<dt><code>none</code></dt>
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<dd><p>None of the argument values are printed. Instead, the value of each argument
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is replaced by <code>…</code>. In this case, the example above now becomes:
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</p>
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<div class="smallexample">
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<pre class="smallexample">#1 0x08048361 in call_me (i=…, s=…, ss=…, u=…, e=…)
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at frame-args.c:23
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</pre></div>
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</dd>
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</dl>
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<p>By default, only scalar arguments are printed. This command can be used
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to configure the debugger to print the value of all arguments, regardless
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of their type. However, it is often advantageous to not print the value
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of more complex parameters. For instance, it reduces the amount of
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information printed in each frame, making the backtrace more readable.
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Also, it improves performance when displaying Ada frames, because
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the computation of large arguments can sometimes be CPU-intensive,
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especially in large applications. Setting <code>print frame-arguments</code>
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to <code>scalars</code> (the default) or <code>none</code> avoids this computation,
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thus speeding up the display of each Ada frame.
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</p>
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</dd>
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<dt><code>show print frame-arguments</code></dt>
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<dd><p>Show how the value of arguments should be displayed when printing a frame.
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</p>
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</dd>
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<dt><code>set print raw frame-arguments on</code></dt>
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<dd><p>Print frame arguments in raw, non pretty-printed, form.
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</p>
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</dd>
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<dt><code>set print raw frame-arguments off</code></dt>
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<dd><p>Print frame arguments in pretty-printed form, if there is a pretty-printer
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for the value (see <a href="Pretty-Printing.html#Pretty-Printing">Pretty Printing</a>),
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otherwise print the value in raw form.
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This is the default.
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</p>
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</dd>
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<dt><code>show print raw frame-arguments</code></dt>
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<dd><p>Show whether to print frame arguments in raw form.
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</p>
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<a name="set-print-entry_002dvalues"></a></dd>
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<dt><code>set print entry-values <var>value</var></code></dt>
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<dd><a name="index-set-print-entry_002dvalues"></a>
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<p>Set printing of frame argument values at function entry. In some cases
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<small>GDB</small> can determine the value of function argument which was passed by
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the function caller, even if the value was modified inside the called function
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and therefore is different. With optimized code, the current value could be
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unavailable, but the entry value may still be known.
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|
</p>
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<p>The default value is <code>default</code> (see below for its description). Older
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<small>GDB</small> behaved as with the setting <code>no</code>. Compilers not supporting
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this feature will behave in the <code>default</code> setting the same way as with the
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<code>no</code> setting.
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</p>
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<p>This functionality is currently supported only by DWARF 2 debugging format and
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the compiler has to produce ‘<samp>DW_TAG_call_site</samp>’ tags. With
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<small>GCC</small>, you need to specify <samp>-O -g</samp> during compilation, to get
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this information.
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</p>
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<p>The <var>value</var> parameter can be one of the following:
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</p>
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<dl compact="compact">
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<dt><code>no</code></dt>
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<dd><p>Print only actual parameter values, never print values from function entry
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point.
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</p><div class="smallexample">
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<pre class="smallexample">#0 equal (val=5)
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#0 different (val=6)
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#0 lost (val=<optimized out>)
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#0 born (val=10)
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#0 invalid (val=<optimized out>)
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</pre></div>
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</dd>
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<dt><code>only</code></dt>
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<dd><p>Print only parameter values from function entry point. The actual parameter
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values are never printed.
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</p><div class="smallexample">
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<pre class="smallexample">#0 equal (val@entry=5)
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#0 different (val@entry=5)
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#0 lost (val@entry=5)
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#0 born (val@entry=<optimized out>)
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#0 invalid (val@entry=<optimized out>)
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</pre></div>
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</dd>
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<dt><code>preferred</code></dt>
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<dd><p>Print only parameter values from function entry point. If value from function
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entry point is not known while the actual value is known, print the actual
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value for such parameter.
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</p><div class="smallexample">
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<pre class="smallexample">#0 equal (val@entry=5)
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#0 different (val@entry=5)
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#0 lost (val@entry=5)
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#0 born (val=10)
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#0 invalid (val@entry=<optimized out>)
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</pre></div>
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</dd>
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<dt><code>if-needed</code></dt>
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<dd><p>Print actual parameter values. If actual parameter value is not known while
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value from function entry point is known, print the entry point value for such
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parameter.
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</p><div class="smallexample">
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|
<pre class="smallexample">#0 equal (val=5)
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#0 different (val=6)
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#0 lost (val@entry=5)
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#0 born (val=10)
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|
#0 invalid (val=<optimized out>)
|
|
</pre></div>
|
|
|
|
</dd>
|
|
<dt><code>both</code></dt>
|
|
<dd><p>Always print both the actual parameter value and its value from function entry
|
|
point, even if values of one or both are not available due to compiler
|
|
optimizations.
|
|
</p><div class="smallexample">
|
|
<pre class="smallexample">#0 equal (val=5, val@entry=5)
|
|
#0 different (val=6, val@entry=5)
|
|
#0 lost (val=<optimized out>, val@entry=5)
|
|
#0 born (val=10, val@entry=<optimized out>)
|
|
#0 invalid (val=<optimized out>, val@entry=<optimized out>)
|
|
</pre></div>
|
|
|
|
</dd>
|
|
<dt><code>compact</code></dt>
|
|
<dd><p>Print the actual parameter value if it is known and also its value from
|
|
function entry point if it is known. If neither is known, print for the actual
|
|
value <code><optimized out></code>. If not in MI mode (see <a href="GDB_002fMI.html#GDB_002fMI">GDB/MI</a>) and if both
|
|
values are known and identical, print the shortened
|
|
<code>param=param@entry=VALUE</code> notation.
|
|
</p><div class="smallexample">
|
|
<pre class="smallexample">#0 equal (val=val@entry=5)
|
|
#0 different (val=6, val@entry=5)
|
|
#0 lost (val@entry=5)
|
|
#0 born (val=10)
|
|
#0 invalid (val=<optimized out>)
|
|
</pre></div>
|
|
|
|
</dd>
|
|
<dt><code>default</code></dt>
|
|
<dd><p>Always print the actual parameter value. Print also its value from function
|
|
entry point, but only if it is known. If not in MI mode (see <a href="GDB_002fMI.html#GDB_002fMI">GDB/MI</a>) and
|
|
if both values are known and identical, print the shortened
|
|
<code>param=param@entry=VALUE</code> notation.
|
|
</p><div class="smallexample">
|
|
<pre class="smallexample">#0 equal (val=val@entry=5)
|
|
#0 different (val=6, val@entry=5)
|
|
#0 lost (val=<optimized out>, val@entry=5)
|
|
#0 born (val=10)
|
|
#0 invalid (val=<optimized out>)
|
|
</pre></div>
|
|
</dd>
|
|
</dl>
|
|
|
|
<p>For analysis messages on possible failures of frame argument values at function
|
|
entry resolution see <a href="Tail-Call-Frames.html#set-debug-entry_002dvalues">set debug entry-values</a>.
|
|
</p>
|
|
</dd>
|
|
<dt><code>show print entry-values</code></dt>
|
|
<dd><p>Show the method being used for printing of frame argument values at function
|
|
entry.
|
|
</p>
|
|
</dd>
|
|
<dt><code>set print repeats <var>number-of-repeats</var></code></dt>
|
|
<dt><code>set print repeats unlimited</code></dt>
|
|
<dd><a name="index-repeated-array-elements"></a>
|
|
<p>Set the threshold for suppressing display of repeated array
|
|
elements. When the number of consecutive identical elements of an
|
|
array exceeds the threshold, <small>GDB</small> prints the string
|
|
<code>"<repeats <var>n</var> times>"</code>, where <var>n</var> is the number of
|
|
identical repetitions, instead of displaying the identical elements
|
|
themselves. Setting the threshold to <code>unlimited</code> or zero will
|
|
cause all elements to be individually printed. The default threshold
|
|
is 10.
|
|
</p>
|
|
</dd>
|
|
<dt><code>show print repeats</code></dt>
|
|
<dd><p>Display the current threshold for printing repeated identical
|
|
elements.
|
|
</p>
|
|
</dd>
|
|
<dt><code>set print null-stop</code></dt>
|
|
<dd><a name="index-NULL-elements-in-arrays"></a>
|
|
<p>Cause <small>GDB</small> to stop printing the characters of an array when the first
|
|
<small>NULL</small> is encountered. This is useful when large arrays actually
|
|
contain only short strings.
|
|
The default is off.
|
|
</p>
|
|
</dd>
|
|
<dt><code>show print null-stop</code></dt>
|
|
<dd><p>Show whether <small>GDB</small> stops printing an array on the first
|
|
<small>NULL</small> character.
|
|
</p>
|
|
</dd>
|
|
<dt><code>set print pretty on</code></dt>
|
|
<dd><a name="index-print-structures-in-indented-form"></a>
|
|
<a name="index-indentation-in-structure-display"></a>
|
|
<p>Cause <small>GDB</small> to print structures in an indented format with one member
|
|
per line, like this:
|
|
</p>
|
|
<div class="smallexample">
|
|
<pre class="smallexample">$1 = {
|
|
next = 0x0,
|
|
flags = {
|
|
sweet = 1,
|
|
sour = 1
|
|
},
|
|
meat = 0x54 "Pork"
|
|
}
|
|
</pre></div>
|
|
|
|
</dd>
|
|
<dt><code>set print pretty off</code></dt>
|
|
<dd><p>Cause <small>GDB</small> to print structures in a compact format, like this:
|
|
</p>
|
|
<div class="smallexample">
|
|
<pre class="smallexample">$1 = {next = 0x0, flags = {sweet = 1, sour = 1}, \
|
|
meat = 0x54 "Pork"}
|
|
</pre></div>
|
|
|
|
<p>This is the default format.
|
|
</p>
|
|
</dd>
|
|
<dt><code>show print pretty</code></dt>
|
|
<dd><p>Show which format <small>GDB</small> is using to print structures.
|
|
</p>
|
|
</dd>
|
|
<dt><code>set print sevenbit-strings on</code></dt>
|
|
<dd><a name="index-eight_002dbit-characters-in-strings"></a>
|
|
<a name="index-octal-escapes-in-strings"></a>
|
|
<p>Print using only seven-bit characters; if this option is set,
|
|
<small>GDB</small> displays any eight-bit characters (in strings or
|
|
character values) using the notation <code>\</code><var>nnn</var>. This setting is
|
|
best if you are working in English (<small>ASCII</small>) and you use the
|
|
high-order bit of characters as a marker or “meta” bit.
|
|
</p>
|
|
</dd>
|
|
<dt><code>set print sevenbit-strings off</code></dt>
|
|
<dd><p>Print full eight-bit characters. This allows the use of more
|
|
international character sets, and is the default.
|
|
</p>
|
|
</dd>
|
|
<dt><code>show print sevenbit-strings</code></dt>
|
|
<dd><p>Show whether or not <small>GDB</small> is printing only seven-bit characters.
|
|
</p>
|
|
</dd>
|
|
<dt><code>set print union on</code></dt>
|
|
<dd><a name="index-unions-in-structures_002c-printing"></a>
|
|
<p>Tell <small>GDB</small> to print unions which are contained in structures
|
|
and other unions. This is the default setting.
|
|
</p>
|
|
</dd>
|
|
<dt><code>set print union off</code></dt>
|
|
<dd><p>Tell <small>GDB</small> not to print unions which are contained in
|
|
structures and other unions. <small>GDB</small> will print <code>"{...}"</code>
|
|
instead.
|
|
</p>
|
|
</dd>
|
|
<dt><code>show print union</code></dt>
|
|
<dd><p>Ask <small>GDB</small> whether or not it will print unions which are contained in
|
|
structures and other unions.
|
|
</p>
|
|
<p>For example, given the declarations
|
|
</p>
|
|
<div class="smallexample">
|
|
<pre class="smallexample">typedef enum {Tree, Bug} Species;
|
|
typedef enum {Big_tree, Acorn, Seedling} Tree_forms;
|
|
typedef enum {Caterpillar, Cocoon, Butterfly}
|
|
Bug_forms;
|
|
|
|
struct thing {
|
|
Species it;
|
|
union {
|
|
Tree_forms tree;
|
|
Bug_forms bug;
|
|
} form;
|
|
};
|
|
|
|
struct thing foo = {Tree, {Acorn}};
|
|
</pre></div>
|
|
|
|
<p>with <code>set print union on</code> in effect ‘<samp>p foo</samp>’ would print
|
|
</p>
|
|
<div class="smallexample">
|
|
<pre class="smallexample">$1 = {it = Tree, form = {tree = Acorn, bug = Cocoon}}
|
|
</pre></div>
|
|
|
|
<p>and with <code>set print union off</code> in effect it would print
|
|
</p>
|
|
<div class="smallexample">
|
|
<pre class="smallexample">$1 = {it = Tree, form = {...}}
|
|
</pre></div>
|
|
|
|
<p><code>set print union</code> affects programs written in C-like languages
|
|
and in Pascal.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
<p>These settings are of interest when debugging C<tt>++</tt> programs:
|
|
</p>
|
|
<dl compact="compact">
|
|
<dd><a name="index-demangling-C_002b_002b-names"></a>
|
|
</dd>
|
|
<dt><code>set print demangle</code></dt>
|
|
<dt><code>set print demangle on</code></dt>
|
|
<dd><p>Print C<tt>++</tt> names in their source form rather than in the encoded
|
|
(“mangled”) form passed to the assembler and linker for type-safe
|
|
linkage. The default is on.
|
|
</p>
|
|
</dd>
|
|
<dt><code>show print demangle</code></dt>
|
|
<dd><p>Show whether C<tt>++</tt> names are printed in mangled or demangled form.
|
|
</p>
|
|
</dd>
|
|
<dt><code>set print asm-demangle</code></dt>
|
|
<dt><code>set print asm-demangle on</code></dt>
|
|
<dd><p>Print C<tt>++</tt> names in their source form rather than their mangled form, even
|
|
in assembler code printouts such as instruction disassemblies.
|
|
The default is off.
|
|
</p>
|
|
</dd>
|
|
<dt><code>show print asm-demangle</code></dt>
|
|
<dd><p>Show whether C<tt>++</tt> names in assembly listings are printed in mangled
|
|
or demangled form.
|
|
</p>
|
|
<a name="index-C_002b_002b-symbol-decoding-style"></a>
|
|
<a name="index-symbol-decoding-style_002c-C_002b_002b"></a>
|
|
<a name="index-set-demangle_002dstyle"></a>
|
|
</dd>
|
|
<dt><code>set demangle-style <var>style</var></code></dt>
|
|
<dd><p>Choose among several encoding schemes used by different compilers to represent
|
|
C<tt>++</tt> names. If you omit <var>style</var>, you will see a list of possible
|
|
formats. The default value is <var>auto</var>, which lets <small>GDB</small> choose a
|
|
decoding style by inspecting your program.
|
|
</p>
|
|
</dd>
|
|
<dt><code>show demangle-style</code></dt>
|
|
<dd><p>Display the encoding style currently in use for decoding C<tt>++</tt> symbols.
|
|
</p>
|
|
</dd>
|
|
<dt><code>set print object</code></dt>
|
|
<dt><code>set print object on</code></dt>
|
|
<dd><a name="index-derived-type-of-an-object_002c-printing"></a>
|
|
<a name="index-display-derived-types"></a>
|
|
<p>When displaying a pointer to an object, identify the <em>actual</em>
|
|
(derived) type of the object rather than the <em>declared</em> type, using
|
|
the virtual function table. Note that the virtual function table is
|
|
required—this feature can only work for objects that have run-time
|
|
type identification; a single virtual method in the object’s declared
|
|
type is sufficient. Note that this setting is also taken into account when
|
|
working with variable objects via MI (see <a href="GDB_002fMI.html#GDB_002fMI">GDB/MI</a>).
|
|
</p>
|
|
</dd>
|
|
<dt><code>set print object off</code></dt>
|
|
<dd><p>Display only the declared type of objects, without reference to the
|
|
virtual function table. This is the default setting.
|
|
</p>
|
|
</dd>
|
|
<dt><code>show print object</code></dt>
|
|
<dd><p>Show whether actual, or declared, object types are displayed.
|
|
</p>
|
|
</dd>
|
|
<dt><code>set print static-members</code></dt>
|
|
<dt><code>set print static-members on</code></dt>
|
|
<dd><a name="index-static-members-of-C_002b_002b-objects"></a>
|
|
<p>Print static members when displaying a C<tt>++</tt> object. The default is on.
|
|
</p>
|
|
</dd>
|
|
<dt><code>set print static-members off</code></dt>
|
|
<dd><p>Do not print static members when displaying a C<tt>++</tt> object.
|
|
</p>
|
|
</dd>
|
|
<dt><code>show print static-members</code></dt>
|
|
<dd><p>Show whether C<tt>++</tt> static members are printed or not.
|
|
</p>
|
|
</dd>
|
|
<dt><code>set print pascal_static-members</code></dt>
|
|
<dt><code>set print pascal_static-members on</code></dt>
|
|
<dd><a name="index-static-members-of-Pascal-objects"></a>
|
|
<a name="index-Pascal-objects_002c-static-members-display"></a>
|
|
<p>Print static members when displaying a Pascal object. The default is on.
|
|
</p>
|
|
</dd>
|
|
<dt><code>set print pascal_static-members off</code></dt>
|
|
<dd><p>Do not print static members when displaying a Pascal object.
|
|
</p>
|
|
</dd>
|
|
<dt><code>show print pascal_static-members</code></dt>
|
|
<dd><p>Show whether Pascal static members are printed or not.
|
|
</p>
|
|
</dd>
|
|
<dt><code>set print vtbl</code></dt>
|
|
<dt><code>set print vtbl on</code></dt>
|
|
<dd><a name="index-pretty-print-C_002b_002b-virtual-function-tables"></a>
|
|
<a name="index-virtual-functions-_0028C_002b_002b_0029-display"></a>
|
|
<a name="index-VTBL-display"></a>
|
|
<p>Pretty print C<tt>++</tt> virtual function tables. The default is off.
|
|
(The <code>vtbl</code> commands do not work on programs compiled with the HP
|
|
ANSI C<tt>++</tt> compiler (<code>aCC</code>).)
|
|
</p>
|
|
</dd>
|
|
<dt><code>set print vtbl off</code></dt>
|
|
<dd><p>Do not pretty print C<tt>++</tt> virtual function tables.
|
|
</p>
|
|
</dd>
|
|
<dt><code>show print vtbl</code></dt>
|
|
<dd><p>Show whether C<tt>++</tt> virtual function tables are pretty printed, or not.
|
|
</p></dd>
|
|
</dl>
|
|
|
|
<hr>
|
|
<div class="header">
|
|
<p>
|
|
Next: <a href="Pretty-Printing.html#Pretty-Printing" accesskey="n" rel="next">Pretty Printing</a>, Previous: <a href="Auto-Display.html#Auto-Display" accesskey="p" rel="prev">Auto Display</a>, Up: <a href="Data.html#Data" accesskey="u" rel="up">Data</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>
|
|
|
|
|
|
|
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</body>
|
|
</html>
|