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<title>Debugging with GDB: Lazy Strings In Python</title>
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<a name="Lazy-Strings-In-Python"></a>
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<a name="Python-representation-of-lazy-strings_002e"></a>
<h4 class="subsubsection">23.2.2.31 Python representation of lazy strings.</h4>
<a name="index-lazy-strings-in-python"></a>
<a name="index-gdb_002eLazyString"></a>
<p>A <em>lazy string</em> is a string whose contents is not retrieved or
encoded until it is needed.
</p>
<p>A <code>gdb.LazyString</code> is represented in <small>GDB</small> as an
<code>address</code> that points to a region of memory, an <code>encoding</code>
that will be used to encode that region of memory, and a <code>length</code>
to delimit the region of memory that represents the string. The
difference between a <code>gdb.LazyString</code> and a string wrapped within
a <code>gdb.Value</code> is that a <code>gdb.LazyString</code> will be treated
differently by <small>GDB</small> when printing. A <code>gdb.LazyString</code> is
retrieved and encoded during printing, while a <code>gdb.Value</code>
wrapping a string is immediately retrieved and encoded on creation.
</p>
<p>A <code>gdb.LazyString</code> object has the following functions:
</p>
<dl>
<dt><a name="index-LazyString_002evalue"></a>Function: <strong>LazyString.value</strong> <em>()</em></dt>
<dd><p>Convert the <code>gdb.LazyString</code> to a <code>gdb.Value</code>. This value
will point to the string in memory, but will lose all the delayed
retrieval, encoding and handling that <small>GDB</small> applies to a
<code>gdb.LazyString</code>.
</p></dd></dl>
<dl>
<dt><a name="index-LazyString_002eaddress"></a>Variable: <strong>LazyString.address</strong></dt>
<dd><p>This attribute holds the address of the string. This attribute is not
writable.
</p></dd></dl>
<dl>
<dt><a name="index-LazyString_002elength"></a>Variable: <strong>LazyString.length</strong></dt>
<dd><p>This attribute holds the length of the string in characters. If the
length is -1, then the string will be fetched and encoded up to the
first null of appropriate width. This attribute is not writable.
</p></dd></dl>
<dl>
<dt><a name="index-LazyString_002eencoding"></a>Variable: <strong>LazyString.encoding</strong></dt>
<dd><p>This attribute holds the encoding that will be applied to the string
when the string is printed by <small>GDB</small>. If the encoding is not
set, or contains an empty string, then <small>GDB</small> will select the
most appropriate encoding when the string is printed. This attribute
is not writable.
</p></dd></dl>
<dl>
<dt><a name="index-LazyString_002etype"></a>Variable: <strong>LazyString.type</strong></dt>
<dd><p>This attribute holds the type that is represented by the lazy string&rsquo;s
type. For a lazy string this will always be a pointer type. To
resolve this to the lazy string&rsquo;s character type, use the type&rsquo;s
<code>target</code> method. See <a href="Types-In-Python.html#Types-In-Python">Types In Python</a>. This attribute is not
writable.
</p></dd></dl>
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