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17<title>Debugging with GDB: Lazy Strings In Python</title>
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64<a name="Lazy-Strings-In-Python"></a>
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66<p>
67Next: <a href="Architectures-In-Python.html#Architectures-In-Python" accesskey="n" rel="next">Architectures In Python</a>, Previous: <a href="Finish-Breakpoints-in-Python.html#Finish-Breakpoints-in-Python" accesskey="p" rel="previous">Finish Breakpoints in Python</a>, Up: <a href="Python-API.html#Python-API" accesskey="u" rel="up">Python API</a> &nbsp; [<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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70<a name="Python-representation-of-lazy-strings"></a>
71<h4 class="subsubsection">23.2.2.32 Python representation of lazy strings</h4>
72
73<a name="index-lazy-strings-in-python"></a>
74<a name="index-gdb_002eLazyString"></a>
75
76<p>A <em>lazy string</em> is a string whose contents is not retrieved or
77encoded until it is needed.
78</p>
79<p>A <code>gdb.LazyString</code> is represented in <small>GDB</small> as an
80<code>address</code> that points to a region of memory, an <code>encoding</code>
81that will be used to encode that region of memory, and a <code>length</code>
82to delimit the region of memory that represents the string.  The
83difference between a <code>gdb.LazyString</code> and a string wrapped within
84a <code>gdb.Value</code> is that a <code>gdb.LazyString</code> will be treated
85differently by <small>GDB</small> when printing.  A <code>gdb.LazyString</code> is
86retrieved and encoded during printing, while a <code>gdb.Value</code>
87wrapping a string is immediately retrieved and encoded on creation.
88</p>
89<p>A <code>gdb.LazyString</code> object has the following functions:
90</p>
91<dl>
92<dt><a name="index-LazyString_002evalue"></a>Function: <strong>LazyString.value</strong> <em>()</em></dt>
93<dd><p>Convert the <code>gdb.LazyString</code> to a <code>gdb.Value</code>.  This value
94will point to the string in memory, but will lose all the delayed
95retrieval, encoding and handling that <small>GDB</small> applies to a
96<code>gdb.LazyString</code>.
97</p></dd></dl>
98
99<dl>
100<dt><a name="index-LazyString_002eaddress"></a>Variable: <strong>LazyString.address</strong></dt>
101<dd><p>This attribute holds the address of the string.  This attribute is not
102writable.
103</p></dd></dl>
104
105<dl>
106<dt><a name="index-LazyString_002elength"></a>Variable: <strong>LazyString.length</strong></dt>
107<dd><p>This attribute holds the length of the string in characters.  If the
108length is -1, then the string will be fetched and encoded up to the
109first null of appropriate width.  This attribute is not writable.
110</p></dd></dl>
111
112<dl>
113<dt><a name="index-LazyString_002eencoding"></a>Variable: <strong>LazyString.encoding</strong></dt>
114<dd><p>This attribute holds the encoding that will be applied to the string
115when the string is printed by <small>GDB</small>.  If the encoding is not
116set, or contains an empty string,  then <small>GDB</small> will select the
117most appropriate encoding when the string is printed.  This attribute
118is not writable.
119</p></dd></dl>
120
121<dl>
122<dt><a name="index-LazyString_002etype"></a>Variable: <strong>LazyString.type</strong></dt>
123<dd><p>This attribute holds the type that is represented by the lazy string&rsquo;s
124type.  For a lazy string this is a pointer or array type.  To
125resolve this to the lazy string&rsquo;s character type, use the type&rsquo;s
126<code>target</code> method.  See <a href="Types-In-Python.html#Types-In-Python">Types In Python</a>.  This attribute is not
127writable.
128</p></dd></dl>
129
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