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<a name="Progspaces-In-Python"></a>
<div class="header">
<p>
Next: <a href="Objfiles-In-Python.html#Objfiles-In-Python" accesskey="n" rel="next">Objfiles In Python</a>, Previous: <a href="Functions-In-Python.html#Functions-In-Python" accesskey="p" rel="prev">Functions 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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<hr>
<a name="Program-Spaces-In-Python"></a>
<h4 class="subsubsection">23.2.2.23 Program Spaces In Python</h4>
<a name="index-progspaces-in-python"></a>
<a name="index-gdb_002eProgspace"></a>
<a name="index-Progspace"></a>
<p>A program space, or <em>progspace</em>, represents a symbolic view
of an address space.
It consists of all of the objfiles of the program.
See <a href="Objfiles-In-Python.html#Objfiles-In-Python">Objfiles In Python</a>.
See <a href="Inferiors-and-Programs.html#Inferiors-and-Programs">program spaces</a>, for more details
about program spaces.
</p>
<p>The following progspace-related functions are available in the
<code>gdb</code> module:
</p>
<a name="index-gdb_002ecurrent_005fprogspace"></a>
<dl>
<dt><a name="index-gdb_002ecurrent_005fprogspace-1"></a>Function: <strong>gdb.current_progspace</strong> <em>()</em></dt>
<dd><p>This function returns the program space of the currently selected inferior.
See <a href="Inferiors-and-Programs.html#Inferiors-and-Programs">Inferiors and Programs</a>. This is identical to
<code>gdb.selected_inferior().progspace</code> (see <a href="Inferiors-In-Python.html#Inferiors-In-Python">Inferiors In Python</a>) and is
included for historical compatibility.
</p></dd></dl>
<a name="index-gdb_002eprogspaces"></a>
<dl>
<dt><a name="index-gdb_002eprogspaces-1"></a>Function: <strong>gdb.progspaces</strong> <em>()</em></dt>
<dd><p>Return a sequence of all the progspaces currently known to <small>GDB</small>.
</p></dd></dl>
<p>Each progspace is represented by an instance of the <code>gdb.Progspace</code>
class.
</p>
<dl>
<dt><a name="index-Progspace_002efilename"></a>Variable: <strong>Progspace.filename</strong></dt>
<dd><p>The file name of the progspace as a string.
</p></dd></dl>
<dl>
<dt><a name="index-Progspace_002epretty_005fprinters"></a>Variable: <strong>Progspace.pretty_printers</strong></dt>
<dd><p>The <code>pretty_printers</code> attribute is a list of functions. It is
used to look up pretty-printers. A <code>Value</code> is passed to each
function in order; if the function returns <code>None</code>, then the
search continues. Otherwise, the return value should be an object
which is used to format the value. See <a href="Pretty-Printing-API.html#Pretty-Printing-API">Pretty Printing API</a>, for more
information.
</p></dd></dl>
<dl>
<dt><a name="index-Progspace_002etype_005fprinters"></a>Variable: <strong>Progspace.type_printers</strong></dt>
<dd><p>The <code>type_printers</code> attribute is a list of type printer objects.
See <a href="Type-Printing-API.html#Type-Printing-API">Type Printing API</a>, for more information.
</p></dd></dl>
<dl>
<dt><a name="index-Progspace_002eframe_005ffilters"></a>Variable: <strong>Progspace.frame_filters</strong></dt>
<dd><p>The <code>frame_filters</code> attribute is a dictionary of frame filter
objects. See <a href="Frame-Filter-API.html#Frame-Filter-API">Frame Filter API</a>, for more information.
</p></dd></dl>
<p>A program space has the following methods:
</p>
<a name="index-Progspace_002eblock_005ffor_005fpc"></a>
<dl>
<dt><a name="index-Progspace_002eblock_005ffor_005fpc-1"></a>Function: <strong>Progspace.block_for_pc</strong> <em>(pc)</em></dt>
<dd><p>Return the innermost <code>gdb.Block</code> containing the given <var>pc</var>
value. If the block cannot be found for the <var>pc</var> value specified,
the function will return <code>None</code>.
</p></dd></dl>
<a name="index-Progspace_002efind_005fpc_005fline"></a>
<dl>
<dt><a name="index-Progspace_002efind_005fpc_005fline-1"></a>Function: <strong>Progspace.find_pc_line</strong> <em>(pc)</em></dt>
<dd><p>Return the <code>gdb.Symtab_and_line</code> object corresponding to the
<var>pc</var> value. See <a href="Symbol-Tables-In-Python.html#Symbol-Tables-In-Python">Symbol Tables In Python</a>. If an invalid value
of <var>pc</var> is passed as an argument, then the <code>symtab</code> and
<code>line</code> attributes of the returned <code>gdb.Symtab_and_line</code>
object will be <code>None</code> and 0 respectively.
</p></dd></dl>
<a name="index-Progspace_002eis_005fvalid"></a>
<dl>
<dt><a name="index-Progspace_002eis_005fvalid-1"></a>Function: <strong>Progspace.is_valid</strong> <em>()</em></dt>
<dd><p>Returns <code>True</code> if the <code>gdb.Progspace</code> object is valid,
<code>False</code> if not. A <code>gdb.Progspace</code> object can become invalid
if the program space file it refers to is not referenced by any
inferior. All other <code>gdb.Progspace</code> methods will throw an
exception if it is invalid at the time the method is called.
</p></dd></dl>
<a name="index-Progspace_002eobjfiles"></a>
<dl>
<dt><a name="index-Progspace_002eobjfiles-1"></a>Function: <strong>Progspace.objfiles</strong> <em>()</em></dt>
<dd><p>Return a sequence of all the objfiles referenced by this program
space. See <a href="Objfiles-In-Python.html#Objfiles-In-Python">Objfiles In Python</a>.
</p></dd></dl>
<a name="index-Progspace_002esolib_005fname"></a>
<dl>
<dt><a name="index-Progspace_002esolib_005fname-1"></a>Function: <strong>Progspace.solib_name</strong> <em>(address)</em></dt>
<dd><p>Return the name of the shared library holding the given <var>address</var>
as a string, or <code>None</code>.
</p></dd></dl>
<p>One may add arbitrary attributes to <code>gdb.Progspace</code> objects
in the usual Python way.
This is useful if, for example, one needs to do some extra record keeping
associated with the program space.
</p>
<p>In this contrived example, we want to perform some processing when
an objfile with a certain symbol is loaded, but we only want to do
this once because it is expensive. To achieve this we record the results
with the program space because we can&rsquo;t predict when the desired objfile
will be loaded.
</p>
<div class="smallexample">
<pre class="smallexample">(gdb) python
def clear_objfiles_handler(event):
event.progspace.expensive_computation = None
def expensive(symbol):
&quot;&quot;&quot;A mock routine to perform an &quot;expensive&quot; computation on symbol.&quot;&quot;&quot;
print &quot;Computing the answer to the ultimate question ...&quot;
return 42
def new_objfile_handler(event):
objfile = event.new_objfile
progspace = objfile.progspace
if not hasattr(progspace, 'expensive_computation') or \
progspace.expensive_computation is None:
# We use 'main' for the symbol to keep the example simple.
# Note: There's no current way to constrain the lookup
# to one objfile.
symbol = gdb.lookup_global_symbol('main')
if symbol is not None:
progspace.expensive_computation = expensive(symbol)
gdb.events.clear_objfiles.connect(clear_objfiles_handler)
gdb.events.new_objfile.connect(new_objfile_handler)
end
(gdb) file /tmp/hello
Reading symbols from /tmp/hello...done.
Computing the answer to the ultimate question ...
(gdb) python print gdb.current_progspace().expensive_computation
42
(gdb) run
Starting program: /tmp/hello
Hello.
[Inferior 1 (process 4242) exited normally]
</pre></div>
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Next: <a href="Objfiles-In-Python.html#Objfiles-In-Python" accesskey="n" rel="next">Objfiles In Python</a>, Previous: <a href="Functions-In-Python.html#Functions-In-Python" accesskey="p" rel="prev">Functions 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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