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 <a name="Symbols-In-Guile"></a>
 <div class="header">
 <p>
 Next: <a href="Symbol-Tables-In-Guile.html#Symbol-Tables-In-Guile" accesskey="n" rel="next">Symbol Tables In Guile</a>, Previous: <a href="Blocks-In-Guile.html#Blocks-In-Guile" accesskey="p" rel="prev">Blocks In Guile</a>, Up: <a href="Guile-API.html#Guile-API" accesskey="u" rel="up">Guile 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>
 </div>
 <hr>
 <a name="Guile-representation-of-Symbols_002e"></a>
 <h4 class="subsubsection">23.3.3.17 Guile representation of Symbols.</h4>

 <a name="index-symbols-in-guile"></a>
 <a name="index-_003cgdb_003asymbol_003e"></a>

 <p><small>GDB</small> represents every variable, function and type as an
 entry in a symbol table.  See <a href="Symbols.html#Symbols">Examining the Symbol Table</a>.
 Guile represents these symbols in <small>GDB</small> with the
 <code>&lt;gdb:symbol&gt;</code> object.
 </p>
 <p>The following symbol-related procedures are provided by the
 <code>(gdb)</code> module:
 </p>
 <dl>
 <dt><a name="index-symbol_003f"></a>Scheme Procedure: <strong>symbol?</strong> <em>object</em></dt>
 <dd><p>Return <code>#t</code> if <var>object</var> is an object of type <code>&lt;gdb:symbol&gt;</code>.
 Otherwise return <code>#f</code>.
 </p></dd></dl>

 <dl>
 <dt><a name="index-symbol_002dvalid_003f"></a>Scheme Procedure: <strong>symbol-valid?</strong> <em>symbol</em></dt>
 <dd><p>Return <code>#t</code> if the <code>&lt;gdb:symbol&gt;</code> object is valid,
 <code>#f</code> if not.  A <code>&lt;gdb:symbol&gt;</code> object can become invalid if
 the symbol it refers to does not exist in <small>GDB</small> any longer.
 All other <code>&lt;gdb:symbol&gt;</code> procedures will throw an exception if it is
 invalid at the time the procedure is called.
 </p></dd></dl>

 <dl>
 <dt><a name="index-symbol_002dtype"></a>Scheme Procedure: <strong>symbol-type</strong> <em>symbol</em></dt>
 <dd><p>Return the type of <var>symbol</var> or <code>#f</code> if no type is recorded.
 The result is an object of type <code>&lt;gdb:type&gt;</code>.
 See <a href="Types-In-Guile.html#Types-In-Guile">Types In Guile</a>.
 </p></dd></dl>

 <dl>
 <dt><a name="index-symbol_002dsymtab"></a>Scheme Procedure: <strong>symbol-symtab</strong> <em>symbol</em></dt>
 <dd><p>Return the symbol table in which <var>symbol</var> appears.
 The result is an object of type <code>&lt;gdb:symtab&gt;</code>.
 See <a href="Symbol-Tables-In-Guile.html#Symbol-Tables-In-Guile">Symbol Tables In Guile</a>.
 </p></dd></dl>

 <dl>
 <dt><a name="index-symbol_002dline"></a>Scheme Procedure: <strong>symbol-line</strong> <em>symbol</em></dt>
 <dd><p>Return the line number in the source code at which <var>symbol</var> was defined.
 This is an integer.
 </p></dd></dl>

 <dl>
 <dt><a name="index-symbol_002dname"></a>Scheme Procedure: <strong>symbol-name</strong> <em>symbol</em></dt>
 <dd><p>Return the name of <var>symbol</var> as a string.
 </p></dd></dl>

 <dl>
 <dt><a name="index-symbol_002dlinkage_002dname"></a>Scheme Procedure: <strong>symbol-linkage-name</strong> <em>symbol</em></dt>
 <dd><p>Return the name of <var>symbol</var>, as used by the linker (i.e., may be mangled).
 </p></dd></dl>

 <dl>
 <dt><a name="index-symbol_002dprint_002dname"></a>Scheme Procedure: <strong>symbol-print-name</strong> <em>symbol</em></dt>
 <dd><p>Return the name of <var>symbol</var> in a form suitable for output.  This is either
 <code>name</code> or <code>linkage_name</code>, depending on whether the user
 asked <small>GDB</small> to display demangled or mangled names.
 </p></dd></dl>

 <dl>
 <dt><a name="index-symbol_002daddr_002dclass"></a>Scheme Procedure: <strong>symbol-addr-class</strong> <em>symbol</em></dt>
 <dd><p>Return the address class of the symbol.  This classifies how to find the value
 of a symbol.  Each address class is a constant defined in the
 <code>(gdb)</code> module and described later in this chapter.
 </p></dd></dl>

 <dl>
 <dt><a name="index-symbol_002dneeds_002dframe_003f"></a>Scheme Procedure: <strong>symbol-needs-frame?</strong> <em>symbol</em></dt>
 <dd><p>Return <code>#t</code> if evaluating <var>symbol</var>&rsquo;s value requires a frame
 (see <a href="Frames-In-Guile.html#Frames-In-Guile">Frames In Guile</a>) and <code>#f</code> otherwise.  Typically,
 local variables will require a frame, but other symbols will not.
 </p></dd></dl>

 <dl>
 <dt><a name="index-symbol_002dargument_003f"></a>Scheme Procedure: <strong>symbol-argument?</strong> <em>symbol</em></dt>
 <dd><p>Return <code>#t</code> if <var>symbol</var> is an argument of a function.
 Otherwise return <code>#f</code>.
 </p></dd></dl>

 <dl>
 <dt><a name="index-symbol_002dconstant_003f"></a>Scheme Procedure: <strong>symbol-constant?</strong> <em>symbol</em></dt>
 <dd><p>Return <code>#t</code> if <var>symbol</var> is a constant.
 Otherwise return <code>#f</code>.
 </p></dd></dl>

 <dl>
 <dt><a name="index-symbol_002dfunction_003f"></a>Scheme Procedure: <strong>symbol-function?</strong> <em>symbol</em></dt>
 <dd><p>Return <code>#t</code> if <var>symbol</var> is a function or a method.
 Otherwise return <code>#f</code>.
 </p></dd></dl>

 <dl>
 <dt><a name="index-symbol_002dvariable_003f"></a>Scheme Procedure: <strong>symbol-variable?</strong> <em>symbol</em></dt>
 <dd><p>Return <code>#t</code> if <var>symbol</var> is a variable.
 Otherwise return <code>#f</code>.
 </p></dd></dl>

 <dl>
 <dt><a name="index-symbol_002dvalue"></a>Scheme Procedure: <strong>symbol-value</strong> <em>symbol <span class="roman">[</span>#:frame frame<span class="roman">]</span></em></dt>
 <dd><p>Compute the value of <var>symbol</var>, as a <code>&lt;gdb:value&gt;</code>.  For
 functions, this computes the address of the function, cast to the
 appropriate type.  If the symbol requires a frame in order to compute
 its value, then <var>frame</var> must be given.  If <var>frame</var> is not
 given, or if <var>frame</var> is invalid, then an exception is thrown.
 </p></dd></dl>

 <dl>
 <dt><a name="index-lookup_002dsymbol"></a>Scheme Procedure: <strong>lookup-symbol</strong> <em>name <span class="roman">[</span>#:block block<span class="roman">]</span> <span class="roman">[</span>#:domain domain<span class="roman">]</span></em></dt>
 <dd><p>This function searches for a symbol by name.  The search scope can be
 restricted to the parameters defined in the optional domain and block
 arguments.
 </p>
 <p><var>name</var> is the name of the symbol.  It must be a string.  The
 optional <var>block</var> argument restricts the search to symbols visible
 in that <var>block</var>.  The <var>block</var> argument must be a
 <code>&lt;gdb:block&gt;</code> object.  If omitted, the block for the current frame
 is used.  The optional <var>domain</var> argument restricts
 the search to the domain type.  The <var>domain</var> argument must be a
 domain constant defined in the <code>(gdb)</code> module and described later
 in this chapter.
 </p>
 <p>The result is a list of two elements.
 The first element is a <code>&lt;gdb:symbol&gt;</code> object or <code>#f</code> if the symbol
 is not found.
 If the symbol is found, the second element is <code>#t</code> if the symbol
 is a field of a method&rsquo;s object (e.g., <code>this</code> in C<tt>++</tt>),
 otherwise it is <code>#f</code>.
 If the symbol is not found, the second element is <code>#f</code>.
 </p></dd></dl>

 <dl>
 <dt><a name="index-lookup_002dglobal_002dsymbol"></a>Scheme Procedure: <strong>lookup-global-symbol</strong> <em>name <span class="roman">[</span>#:domain domain<span class="roman">]</span></em></dt>
 <dd><p>This function searches for a global symbol by name.
 The search scope can be restricted by the domain argument.
 </p>
 <p><var>name</var> is the name of the symbol.  It must be a string.
 The optional <var>domain</var> argument restricts the search to the domain type.
 The <var>domain</var> argument must be a domain constant defined in the <code>(gdb)</code>
 module and described later in this chapter.
 </p>
 <p>The result is a <code>&lt;gdb:symbol&gt;</code> object or <code>#f</code> if the symbol
 is not found.
 </p></dd></dl>

 <p>The available domain categories in <code>&lt;gdb:symbol&gt;</code> are represented
 as constants in the <code>(gdb)</code> module:
 </p>
 <dl compact="compact">
 <dt><code>SYMBOL_UNDEF_DOMAIN</code>
 <a name="index-SYMBOL_005fUNDEF_005fDOMAIN-1"></a>
 </dt>
 <dd><p>This is used when a domain has not been discovered or none of the
 following domains apply.  This usually indicates an error either
 in the symbol information or in <small>GDB</small>&rsquo;s handling of symbols.
 </p>
 </dd>
 <dt><code>SYMBOL_VAR_DOMAIN</code>
 <a name="index-SYMBOL_005fVAR_005fDOMAIN-1"></a>
 </dt>
 <dd><p>This domain contains variables, function names, typedef names and enum
 type values.
 </p>
 </dd>
 <dt><code>SYMBOL_STRUCT_DOMAIN</code>
 <a name="index-SYMBOL_005fSTRUCT_005fDOMAIN-1"></a>
 </dt>
 <dd><p>This domain holds struct, union and enum type names.
 </p>
 </dd>
 <dt><code>SYMBOL_LABEL_DOMAIN</code>
 <a name="index-SYMBOL_005fLABEL_005fDOMAIN-1"></a>
 </dt>
 <dd><p>This domain contains names of labels (for gotos).
 </p>
 </dd>
 <dt><code>SYMBOL_VARIABLES_DOMAIN</code>
 <a name="index-SYMBOL_005fVARIABLES_005fDOMAIN-1"></a>
 </dt>
 <dd><p>This domain holds a subset of the <code>SYMBOLS_VAR_DOMAIN</code>; it
 contains everything minus functions and types.
 </p>
 </dd>
 <dt><code>SYMBOL_FUNCTION_DOMAIN</code>
 <a name="index-SYMBOL_005fFUNCTION_005fDOMAIN"></a>
 </dt>
 <dd><p>This domain contains all functions.
 </p>
 </dd>
 <dt><code>SYMBOL_TYPES_DOMAIN</code>
 <a name="index-SYMBOL_005fTYPES_005fDOMAIN-1"></a>
 </dt>
 <dd><p>This domain contains all types.
 </p></dd>
 </dl>

 <p>The available address class categories in <code>&lt;gdb:symbol&gt;</code> are represented
 as constants in the <code>gdb</code> module:
 </p>
 <dl compact="compact">
 <dt><code>SYMBOL_LOC_UNDEF</code>
 <a name="index-SYMBOL_005fLOC_005fUNDEF-1"></a>
 </dt>
 <dd><p>If this is returned by address class, it indicates an error either in
 the symbol information or in <small>GDB</small>&rsquo;s handling of symbols.
 </p>
 </dd>
 <dt><code>SYMBOL_LOC_CONST</code>
 <a name="index-SYMBOL_005fLOC_005fCONST-1"></a>
 </dt>
 <dd><p>Value is constant int.
 </p>
 </dd>
 <dt><code>SYMBOL_LOC_STATIC</code>
 <a name="index-SYMBOL_005fLOC_005fSTATIC-1"></a>
 </dt>
 <dd><p>Value is at a fixed address.
 </p>
 </dd>
 <dt><code>SYMBOL_LOC_REGISTER</code>
 <a name="index-SYMBOL_005fLOC_005fREGISTER-1"></a>
 </dt>
 <dd><p>Value is in a register.
 </p>
 </dd>
 <dt><code>SYMBOL_LOC_ARG</code>
 <a name="index-SYMBOL_005fLOC_005fARG-1"></a>
 </dt>
 <dd><p>Value is an argument.  This value is at the offset stored within the
 symbol inside the frame&rsquo;s argument list.
 </p>
 </dd>
 <dt><code>SYMBOL_LOC_REF_ARG</code>
 <a name="index-SYMBOL_005fLOC_005fREF_005fARG-1"></a>
 </dt>
 <dd><p>Value address is stored in the frame&rsquo;s argument list.  Just like
 <code>LOC_ARG</code> except that the value&rsquo;s address is stored at the
 offset, not the value itself.
 </p>
 </dd>
 <dt><code>SYMBOL_LOC_REGPARM_ADDR</code>
 <a name="index-SYMBOL_005fLOC_005fREGPARM_005fADDR-1"></a>
 </dt>
 <dd><p>Value is a specified register.  Just like <code>LOC_REGISTER</code> except
 the register holds the address of the argument instead of the argument
 itself.
 </p>
 </dd>
 <dt><code>SYMBOL_LOC_LOCAL</code>
 <a name="index-SYMBOL_005fLOC_005fLOCAL-1"></a>
 </dt>
 <dd><p>Value is a local variable.
 </p>
 </dd>
 <dt><code>SYMBOL_LOC_TYPEDEF</code>
 <a name="index-SYMBOL_005fLOC_005fTYPEDEF-1"></a>
 </dt>
 <dd><p>Value not used.  Symbols in the domain <code>SYMBOL_STRUCT_DOMAIN</code> all
 have this class.
 </p>
 </dd>
 <dt><code>SYMBOL_LOC_BLOCK</code>
 <a name="index-SYMBOL_005fLOC_005fBLOCK-1"></a>
 </dt>
 <dd><p>Value is a block.
 </p>
 </dd>
 <dt><code>SYMBOL_LOC_CONST_BYTES</code>
 <a name="index-SYMBOL_005fLOC_005fCONST_005fBYTES-1"></a>
 </dt>
 <dd><p>Value is a byte-sequence.
 </p>
 </dd>
 <dt><code>SYMBOL_LOC_UNRESOLVED</code>
 <a name="index-SYMBOL_005fLOC_005fUNRESOLVED-1"></a>
 </dt>
 <dd><p>Value is at a fixed address, but the address of the variable has to be
 determined from the minimal symbol table whenever the variable is
 referenced.
 </p>
 </dd>
 <dt><code>SYMBOL_LOC_OPTIMIZED_OUT</code>
 <a name="index-SYMBOL_005fLOC_005fOPTIMIZED_005fOUT-1"></a>
 </dt>
 <dd><p>The value does not actually exist in the program.
 </p>
 </dd>
 <dt><code>SYMBOL_LOC_COMPUTED</code>
 <a name="index-SYMBOL_005fLOC_005fCOMPUTED-1"></a>
 </dt>
 <dd><p>The value&rsquo;s address is a computed location.
 </p></dd>
 </dl>

 <hr>
 <div class="header">
 <p>
 Next: <a href="Symbol-Tables-In-Guile.html#Symbol-Tables-In-Guile" accesskey="n" rel="next">Symbol Tables In Guile</a>, Previous: <a href="Blocks-In-Guile.html#Blocks-In-Guile" accesskey="p" rel="prev">Blocks In Guile</a>, Up: <a href="Guile-API.html#Guile-API" accesskey="u" rel="up">Guile 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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	<p>
	Next: <a href="Symbol-Tables-In-Guile.html#Symbol-Tables-In-Guile" accesskey="n" rel="next">Symbol Tables In Guile</a>, Previous: <a href="Blocks-In-Guile.html#Blocks-In-Guile" accesskey="p" rel="prev">Blocks In Guile</a>, Up: <a href="Guile-API.html#Guile-API" accesskey="u" rel="up">Guile API</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>
	<hr>
	<a name="Guile-representation-of-Symbols_002e"></a>
	<h4 class="subsubsection">23.3.3.17 Guile representation of Symbols.</h4>

	<a name="index-symbols-in-guile"></a>
	<a name="index-_003cgdb_003asymbol_003e"></a>

	<p><small>GDB</small> represents every variable, function and type as an
	entry in a symbol table. See <a href="Symbols.html#Symbols">Examining the Symbol Table</a>.
	Guile represents these symbols in <small>GDB</small> with the
	<code><gdb:symbol></code> object.
	</p>
	<p>The following symbol-related procedures are provided by the
	<code>(gdb)</code> module:
	</p>
	<dl>
	<dt><a name="index-symbol_003f"></a>Scheme Procedure: <strong>symbol?</strong> <em>object</em></dt>
	<dd><p>Return <code>#t</code> if <var>object</var> is an object of type <code><gdb:symbol></code>.
	Otherwise return <code>#f</code>.
	</p></dd></dl>

	<dl>
	<dt><a name="index-symbol_002dvalid_003f"></a>Scheme Procedure: <strong>symbol-valid?</strong> <em>symbol</em></dt>
	<dd><p>Return <code>#t</code> if the <code><gdb:symbol></code> object is valid,
	<code>#f</code> if not. A <code><gdb:symbol></code> object can become invalid if
	the symbol it refers to does not exist in <small>GDB</small> any longer.
	All other <code><gdb:symbol></code> procedures will throw an exception if it is
	invalid at the time the procedure is called.
	</p></dd></dl>

	<dl>
	<dt><a name="index-symbol_002dtype"></a>Scheme Procedure: <strong>symbol-type</strong> <em>symbol</em></dt>
	<dd><p>Return the type of <var>symbol</var> or <code>#f</code> if no type is recorded.
	The result is an object of type <code><gdb:type></code>.
	See <a href="Types-In-Guile.html#Types-In-Guile">Types In Guile</a>.
	</p></dd></dl>

	<dl>
	<dt><a name="index-symbol_002dsymtab"></a>Scheme Procedure: <strong>symbol-symtab</strong> <em>symbol</em></dt>
	<dd><p>Return the symbol table in which <var>symbol</var> appears.
	The result is an object of type <code><gdb:symtab></code>.
	See <a href="Symbol-Tables-In-Guile.html#Symbol-Tables-In-Guile">Symbol Tables In Guile</a>.
	</p></dd></dl>

	<dl>
	<dt><a name="index-symbol_002dline"></a>Scheme Procedure: <strong>symbol-line</strong> <em>symbol</em></dt>
	<dd><p>Return the line number in the source code at which <var>symbol</var> was defined.
	This is an integer.
	</p></dd></dl>

	<dl>
	<dt><a name="index-symbol_002dname"></a>Scheme Procedure: <strong>symbol-name</strong> <em>symbol</em></dt>
	<dd><p>Return the name of <var>symbol</var> as a string.
	</p></dd></dl>

	<dl>
	<dt><a name="index-symbol_002dlinkage_002dname"></a>Scheme Procedure: <strong>symbol-linkage-name</strong> <em>symbol</em></dt>
	<dd><p>Return the name of <var>symbol</var>, as used by the linker (i.e., may be mangled).
	</p></dd></dl>

	<dl>
	<dt><a name="index-symbol_002dprint_002dname"></a>Scheme Procedure: <strong>symbol-print-name</strong> <em>symbol</em></dt>
	<dd><p>Return the name of <var>symbol</var> in a form suitable for output. This is either
	<code>name</code> or <code>linkage_name</code>, depending on whether the user
	asked <small>GDB</small> to display demangled or mangled names.
	</p></dd></dl>

	<dl>
	<dt><a name="index-symbol_002daddr_002dclass"></a>Scheme Procedure: <strong>symbol-addr-class</strong> <em>symbol</em></dt>
	<dd><p>Return the address class of the symbol. This classifies how to find the value
	of a symbol. Each address class is a constant defined in the
	<code>(gdb)</code> module and described later in this chapter.
	</p></dd></dl>

	<dl>
	<dt><a name="index-symbol_002dneeds_002dframe_003f"></a>Scheme Procedure: <strong>symbol-needs-frame?</strong> <em>symbol</em></dt>
	<dd><p>Return <code>#t</code> if evaluating <var>symbol</var>’s value requires a frame
	(see <a href="Frames-In-Guile.html#Frames-In-Guile">Frames In Guile</a>) and <code>#f</code> otherwise. Typically,
	local variables will require a frame, but other symbols will not.
	</p></dd></dl>

	<dl>
	<dt><a name="index-symbol_002dargument_003f"></a>Scheme Procedure: <strong>symbol-argument?</strong> <em>symbol</em></dt>
	<dd><p>Return <code>#t</code> if <var>symbol</var> is an argument of a function.
	Otherwise return <code>#f</code>.
	</p></dd></dl>

	<dl>
	<dt><a name="index-symbol_002dconstant_003f"></a>Scheme Procedure: <strong>symbol-constant?</strong> <em>symbol</em></dt>
	<dd><p>Return <code>#t</code> if <var>symbol</var> is a constant.
	Otherwise return <code>#f</code>.
	</p></dd></dl>

	<dl>
	<dt><a name="index-symbol_002dfunction_003f"></a>Scheme Procedure: <strong>symbol-function?</strong> <em>symbol</em></dt>
	<dd><p>Return <code>#t</code> if <var>symbol</var> is a function or a method.
	Otherwise return <code>#f</code>.
	</p></dd></dl>

	<dl>
	<dt><a name="index-symbol_002dvariable_003f"></a>Scheme Procedure: <strong>symbol-variable?</strong> <em>symbol</em></dt>
	<dd><p>Return <code>#t</code> if <var>symbol</var> is a variable.
	Otherwise return <code>#f</code>.
	</p></dd></dl>

	<dl>
	<dt><a name="index-symbol_002dvalue"></a>Scheme Procedure: <strong>symbol-value</strong> <em>symbol <span class="roman">[</span>#:frame frame<span class="roman">]</span></em></dt>
	<dd><p>Compute the value of <var>symbol</var>, as a <code><gdb:value></code>. For
	functions, this computes the address of the function, cast to the
	appropriate type. If the symbol requires a frame in order to compute
	its value, then <var>frame</var> must be given. If <var>frame</var> is not
	given, or if <var>frame</var> is invalid, then an exception is thrown.
	</p></dd></dl>

	<dl>
	<dt><a name="index-lookup_002dsymbol"></a>Scheme Procedure: <strong>lookup-symbol</strong> <em>name <span class="roman">[</span>#:block block<span class="roman">]</span> <span class="roman">[</span>#:domain domain<span class="roman">]</span></em></dt>
	<dd><p>This function searches for a symbol by name. The search scope can be
	restricted to the parameters defined in the optional domain and block
	arguments.
	</p>
	<p><var>name</var> is the name of the symbol. It must be a string. The
	optional <var>block</var> argument restricts the search to symbols visible
	in that <var>block</var>. The <var>block</var> argument must be a
	<code><gdb:block></code> object. If omitted, the block for the current frame
	is used. The optional <var>domain</var> argument restricts
	the search to the domain type. The <var>domain</var> argument must be a
	domain constant defined in the <code>(gdb)</code> module and described later
	in this chapter.
	</p>
	<p>The result is a list of two elements.
	The first element is a <code><gdb:symbol></code> object or <code>#f</code> if the symbol
	is not found.
	If the symbol is found, the second element is <code>#t</code> if the symbol
	is a field of a method’s object (e.g., <code>this</code> in C<tt>++</tt>),
	otherwise it is <code>#f</code>.
	If the symbol is not found, the second element is <code>#f</code>.
	</p></dd></dl>

	<dl>
	<dt><a name="index-lookup_002dglobal_002dsymbol"></a>Scheme Procedure: <strong>lookup-global-symbol</strong> <em>name <span class="roman">[</span>#:domain domain<span class="roman">]</span></em></dt>
	<dd><p>This function searches for a global symbol by name.
	The search scope can be restricted by the domain argument.
	</p>
	<p><var>name</var> is the name of the symbol. It must be a string.
	The optional <var>domain</var> argument restricts the search to the domain type.
	The <var>domain</var> argument must be a domain constant defined in the <code>(gdb)</code>
	module and described later in this chapter.
	</p>
	<p>The result is a <code><gdb:symbol></code> object or <code>#f</code> if the symbol
	is not found.
	</p></dd></dl>

	<p>The available domain categories in <code><gdb:symbol></code> are represented
	as constants in the <code>(gdb)</code> module:
	</p>
	<dl compact="compact">
	<dt><code>SYMBOL_UNDEF_DOMAIN</code>
	<a name="index-SYMBOL_005fUNDEF_005fDOMAIN-1"></a>
	</dt>
	<dd><p>This is used when a domain has not been discovered or none of the
	following domains apply. This usually indicates an error either
	in the symbol information or in <small>GDB</small>’s handling of symbols.
	</p>
	</dd>
	<dt><code>SYMBOL_VAR_DOMAIN</code>
	<a name="index-SYMBOL_005fVAR_005fDOMAIN-1"></a>
	</dt>
	<dd><p>This domain contains variables, function names, typedef names and enum
	type values.
	</p>
	</dd>
	<dt><code>SYMBOL_STRUCT_DOMAIN</code>
	<a name="index-SYMBOL_005fSTRUCT_005fDOMAIN-1"></a>
	</dt>
	<dd><p>This domain holds struct, union and enum type names.
	</p>
	</dd>
	<dt><code>SYMBOL_LABEL_DOMAIN</code>
	<a name="index-SYMBOL_005fLABEL_005fDOMAIN-1"></a>
	</dt>
	<dd><p>This domain contains names of labels (for gotos).
	</p>
	</dd>
	<dt><code>SYMBOL_VARIABLES_DOMAIN</code>
	<a name="index-SYMBOL_005fVARIABLES_005fDOMAIN-1"></a>
	</dt>
	<dd><p>This domain holds a subset of the <code>SYMBOLS_VAR_DOMAIN</code>; it
	contains everything minus functions and types.
	</p>
	</dd>
	<dt><code>SYMBOL_FUNCTION_DOMAIN</code>
	<a name="index-SYMBOL_005fFUNCTION_005fDOMAIN"></a>
	</dt>
	<dd><p>This domain contains all functions.
	</p>
	</dd>
	<dt><code>SYMBOL_TYPES_DOMAIN</code>
	<a name="index-SYMBOL_005fTYPES_005fDOMAIN-1"></a>
	</dt>
	<dd><p>This domain contains all types.
	</p></dd>
	</dl>

	<p>The available address class categories in <code><gdb:symbol></code> are represented
	as constants in the <code>gdb</code> module:
	</p>
	<dl compact="compact">
	<dt><code>SYMBOL_LOC_UNDEF</code>
	<a name="index-SYMBOL_005fLOC_005fUNDEF-1"></a>
	</dt>
	<dd><p>If this is returned by address class, it indicates an error either in
	the symbol information or in <small>GDB</small>’s handling of symbols.
	</p>
	</dd>
	<dt><code>SYMBOL_LOC_CONST</code>
	<a name="index-SYMBOL_005fLOC_005fCONST-1"></a>
	</dt>
	<dd><p>Value is constant int.
	</p>
	</dd>
	<dt><code>SYMBOL_LOC_STATIC</code>
	<a name="index-SYMBOL_005fLOC_005fSTATIC-1"></a>
	</dt>
	<dd><p>Value is at a fixed address.
	</p>
	</dd>
	<dt><code>SYMBOL_LOC_REGISTER</code>
	<a name="index-SYMBOL_005fLOC_005fREGISTER-1"></a>
	</dt>
	<dd><p>Value is in a register.
	</p>
	</dd>
	<dt><code>SYMBOL_LOC_ARG</code>
	<a name="index-SYMBOL_005fLOC_005fARG-1"></a>
	</dt>
	<dd><p>Value is an argument. This value is at the offset stored within the
	symbol inside the frame’s argument list.
	</p>
	</dd>
	<dt><code>SYMBOL_LOC_REF_ARG</code>
	<a name="index-SYMBOL_005fLOC_005fREF_005fARG-1"></a>
	</dt>
	<dd><p>Value address is stored in the frame’s argument list. Just like
	<code>LOC_ARG</code> except that the value’s address is stored at the
	offset, not the value itself.
	</p>
	</dd>
	<dt><code>SYMBOL_LOC_REGPARM_ADDR</code>
	<a name="index-SYMBOL_005fLOC_005fREGPARM_005fADDR-1"></a>
	</dt>
	<dd><p>Value is a specified register. Just like <code>LOC_REGISTER</code> except
	the register holds the address of the argument instead of the argument
	itself.
	</p>
	</dd>
	<dt><code>SYMBOL_LOC_LOCAL</code>
	<a name="index-SYMBOL_005fLOC_005fLOCAL-1"></a>
	</dt>
	<dd><p>Value is a local variable.
	</p>
	</dd>
	<dt><code>SYMBOL_LOC_TYPEDEF</code>
	<a name="index-SYMBOL_005fLOC_005fTYPEDEF-1"></a>
	</dt>
	<dd><p>Value not used. Symbols in the domain <code>SYMBOL_STRUCT_DOMAIN</code> all
	have this class.
	</p>
	</dd>
	<dt><code>SYMBOL_LOC_BLOCK</code>
	<a name="index-SYMBOL_005fLOC_005fBLOCK-1"></a>
	</dt>
	<dd><p>Value is a block.
	</p>
	</dd>
	<dt><code>SYMBOL_LOC_CONST_BYTES</code>
	<a name="index-SYMBOL_005fLOC_005fCONST_005fBYTES-1"></a>
	</dt>
	<dd><p>Value is a byte-sequence.
	</p>
	</dd>
	<dt><code>SYMBOL_LOC_UNRESOLVED</code>
	<a name="index-SYMBOL_005fLOC_005fUNRESOLVED-1"></a>
	</dt>
	<dd><p>Value is at a fixed address, but the address of the variable has to be
	determined from the minimal symbol table whenever the variable is
	referenced.
	</p>
	</dd>
	<dt><code>SYMBOL_LOC_OPTIMIZED_OUT</code>
	<a name="index-SYMBOL_005fLOC_005fOPTIMIZED_005fOUT-1"></a>
	</dt>
	<dd><p>The value does not actually exist in the program.
	</p>
	</dd>
	<dt><code>SYMBOL_LOC_COMPUTED</code>
	<a name="index-SYMBOL_005fLOC_005fCOMPUTED-1"></a>
	</dt>
	<dd><p>The value’s address is a computed location.
	</p></dd>
	</dl>

	<hr>
	<div class="header">
	<p>
	Next: <a href="Symbol-Tables-In-Guile.html#Symbol-Tables-In-Guile" accesskey="n" rel="next">Symbol Tables In Guile</a>, Previous: <a href="Blocks-In-Guile.html#Blocks-In-Guile" accesskey="p" rel="prev">Blocks In Guile</a>, Up: <a href="Guile-API.html#Guile-API" accesskey="u" rel="up">Guile API</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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