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<H2><A NAME="SECTION0051140000000000000000"> </A>
<BR>
3.11.4 The interpreter stack
</H2>
<P>
When the following functions return ``frame records,'' each record
is a tuple of six items: the frame object, the filename,
the line number of the current line, the function name, a list of
lines of context from the source code, and the index of the current
line within that list.
The optional <var>context</var> argument specifies the number of lines of
context to return, which are centered around the current line.
<P>
<span class="warning"><b class="label">Warning:</b>
Keeping references to frame objects, as found in
the first element of the frame records these functions return, can
cause your program to create reference cycles. Once a reference cycle
has been created, the lifespan of all objects which can be accessed
from the objects which form the cycle can become much longer even if
Python's optional cycle detector is enabled. If such cycles must be
created, it is important to ensure they are explicitly broken to avoid
the delayed destruction of objects and increased memory consumption
which occurs.</span>
<P>
<dl><dt><b><a name="l2h-485"><tt class="function">getframeinfo</tt></a></b>(<var>frame</var><big>[</big><var>, context</var><big>]</big>)
<dd>
Get information about a frame or traceback object. A 5-tuple
is returned, the last five elements of the frame's frame record.
The optional second argument specifies the number of lines of context
to return, which are centered around the current line.
</dl>
<P>
<dl><dt><b><a name="l2h-486"><tt class="function">getouterframes</tt></a></b>(<var>frame</var><big>[</big><var>, context</var><big>]</big>)
<dd>
Get a list of frame records for a frame and all higher (calling)
frames.
</dl>
<P>
<dl><dt><b><a name="l2h-487"><tt class="function">getinnerframes</tt></a></b>(<var>traceback</var><big>[</big><var>, context</var><big>]</big>)
<dd>
Get a list of frame records for a traceback's frame and all lower
frames.
</dl>
<P>
<dl><dt><b><a name="l2h-488"><tt class="function">currentframe</tt></a></b>()
<dd>
Return the frame object for the caller's stack frame.
</dl>
<P>
<dl><dt><b><a name="l2h-489"><tt class="function">stack</tt></a></b>(<big>[</big><var>context</var><big>]</big>)
<dd>
Return a list of frame records for the stack above the caller's
frame.
</dl>
<P>
<dl><dt><b><a name="l2h-490"><tt class="function">trace</tt></a></b>(<big>[</big><var>context</var><big>]</big>)
<dd>
Return a list of frame records for the stack below the current
exception.
</dl>
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<span class="release-info">Release 2.2, documentation updated on December 21, 2001.</span>
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