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<h3>Converting Data from Python to C</h3>
<p>The following functions are used to convert arguments passed from Python to C.</p>

<PRE>

<B>int PyArg_ParseTuple(PyObject *</b> <b><i>args</i></B><B>, char *</B> <B><i>format</i></b><b>, ...);</B> </PRE>

<p>Parses a tuple of objects in <i><tt class="monofont">args</tt></i>
  into a series of C variables. <i><tt class="monofont">format</Tt></i>
  is a format string containing zero or more of the specifier strings from Table B.1, which describes the expected contents of <I><tt cLass="monofont">args</tT></i>
. All the remaining arguments contain the addresses of C variables into which the results will be placed. The order and types of these arguments must match the specifiers used in <i><tT CLAss="monofont">format</tt></I>
  and use the C datatypes listed in <A HRef="125#2.html">Table B.1</a>. Zero is returned if the arguments could not be parsed.</p>

<PRE>

<B>int PyArg_ParseTupleAndKeywords(PyObject *</b> <b><i>args</i></B><B>, PyObject *</B> <B><i>kwdict</i></b><b>,</b> 
                                <b>char *</b> <b><i>format</i></b><b>, char **</b> <b><i>kwlist</i></b><b>, ...);</b> </pRe>

<p>Parses both a tuple of arguments and a dictionary containing keyword arguments contained in <I><tt cLass="monofont">kwdict</tT></i>
  . <i><tT CLAss="monofont">format</tt></I>
 has the same meaning as for <TT Class="monofont">PyArg_ParseTuple()</TT>. The only difference is that <I><Tt claSS="monofont">kwlist</TT></i>
  is a null-terminated list of strings containing the names of all the arguments. Returns <tt class="monofont">1</tt>  on success, <tt class="monofont">0</tt> on error.</p>

<P><i>Note:</i> In Table B.1, results of a conversion (for example, in <Tt clAss="monofont">char *</tt><I><tt cLASS="monofont">r</tt></i>
 or <tT CLAss="monofont">char **</tt><I><TT Class="monofont">r</TT></I>
) are always placed in the parameter labeled <I><tt class="monofont">r</tt></i>
. When applicable, a length is stored in <i><tt class="monofont">len</tt></I>
.</p>

<a Name="2"></A><p><tabLe boRDER="1" cellSPACing="0" cELLPaddiNG="1" WIdth="100%">
<caption><h5>Table燘.1.  Base Format Specifiers and Associated C Datatypes for <tt class="monofont">PyArg_Parse*</tt></H5></caPtioN><colgRoup SPAN="3">
<tr>
<th VALIgn="top">
<foNT SIze="2">
<p><b>Format</B></P>
</FOnt></th>
<th valign="top">
<font size="2">
<P><b>Python Type</b></P>
</fonT></th>
<th ValiGN="top">
<FOnt siZE="2">
<P><B>C Type</b></p>
</foNT></TH>
</tr>
<tr>
<TD VAlign="top">
<font size="2">
<p><tt class="monofont">"s"</Tt></p>
</Font></Td>
<td vAligN="top">
<FONt sizE="2">
<P>String or Unicode</P>
</Font></tD>
<TD ValigN="top">
<FONt size="2">
<p><tt class="monofont">char **</tt><i><tt clAss="monofont">r</Tt></i>
</p>
</Font></tD>
</tr>
<tR>
<TD ValigN="top">
<FONt sizE="2">
<P><TT clasS="monofont">"s#"</TT></P>
</font></td>
<td valign="top">
<font siZe="2">
<p>String or Unicode</P>
</fonT></td>
<td ValiGN="top">
<FOnt siZE="2">
<P><Tt claSS="monofont">char **</TT><i><tt cLASS="monofont">r</tt></i>
<tt class="monofont">, int *</tt><i><tt class="monofont">len</Tt></i>
</P>
</fonT></td>
</tr>
<Tr>
<td VALIgn="top">
<foNT SIze="2">
<p><tT CLAss="monofont">"z"</tt></P>
</FONt></td>
<td valign="top">
<font size="2">
<p>String, Unicode, or None</P>
</foNt></td>
<Td valIgn="top">
<fONT Size="2">
<p><TT CLass="monofont">char **</tT><I><TT clasS="monofont">r</TT></I>
</p>
</font></td>
</tr>
<tr>
<td valign="top">
<fOnt Size="2">
<P><tt clAss="monofont">"z#"</tT></P>
</FOnt></td>
<TD VAlign="top">
<FONT size="2">
<P>String, Unicode, or None</P>
</FOnt></td>
<td valign="top">
<font size="2">
<P><tt ClasS="monofont">char **r, int *</tt><i><tT claSS="monofont">len</TT></i>
</p>
</foNT></TD>
</tr>
<tr>
<TD VAlign="top">
<FONT size="2">
<p><tt class="monofont">"u"</tt></p>
</font></tD>
<td ValiGn="top">
<fonT sizE="2">
<P>Unicode</P>
</Font></tD>
<TD ValigN="top">
<FONt sizE="2">
<P><TT class="monofont">Py_UNICODE **</tt><i><tt class="monofont">r</tt></i>
</p>
</fOnt></Td>
</tr>
<Tr>
<td vAligN="top">
<FONt sizE="2">
<P><TT clasS="monofont">"u#"</TT></P>
</font></TD>
<TD valign="top">
<font size="2">
<p>Unicode</p>
</font></Td>
<tD valIgn="top">
<foNt siZE="2">
<P><Tt claSS="monofont">Py_UNICODE **</TT><i><tt cLASS="monofont">r</tt></i>
<tT CLAss="monofont">, int *</tt><i><tt class="monofont">len</tt></i>
</p>
</font></Td>
</tR>
<tr>
<tD valiGn="top">
<foNT SIze="2">
<p><tT CLAss="monofont">"es"</tt></P>
</FONt></td>
<tD VALign="top">
<font size="2">
<p>String, Unicode, or buffer</p>
</font></td>
<tD vaLign="top">
<Font sIze="2">
<p><TT CLass="monofont">const char *</tT><I><TT clasS="monofont">enc</TT></I>
<tt clASS="monofont">, char **</Tt><i><tt class="monofont">r</tt></i>
</p>
</font></td>
</tR>
<tr>
<Td vaLign="top">
<fOnt sIZE="2">
<P><tt clASS="monofont">"es#"</Tt></p>
</foNT></TD>
<td vaLIGN="top">
<font size="2">
<p>String, Unicode, or buffer</p>
</font></td>
<td vaLigN="top">
<fonT size="2">
<P><tt cLASS="monofont">const char *</tt><i><tT CLAss="monofont">enc</tt></I>
<TT Class="monofont">, char **</TT><I><Tt class="monofont">r</tt></i>
<tt class="monofont">, int *</tt><i><tT clAss="monofont">len</tT></i>
</p>
</foNt></td>
</TR>
<TR>
<td vaLIGN="top">
<font SIZE="2">
<p><tt cLASS="monofont">"b"</tt></p>
</font></td>
<td valign="top">
<fonT siZe="2">
<p>Integer</p>
</Font></tD>
<td vALIGn="top">
<fonT SIZe="2">
<p><tt CLASs="monofont">char *</tt><i><TT CLass="monofont">r</tt></i>
</p>
</font></td>
</tr>
<tr>
<td vAliGn="top">
<foNt sizE="2">
<p><tt CLASs="monofont">"h"</tt></p>
</FONT></td>
<td VALIgn="top">
<foNT SIze="2">
<p>Integer</p>
</font></td>
<td valign="top">
<foNt sIze="2">
<p><Tt claSs="monofont">short *</tt><I><TT Class="monofont">r</TT></I>
</P>
</font></TD>
</TR>
<tr>
<td VALIgn="top">
<font size="2">
<p><tt class="monofont">"i"</tt></P>
</foNt></td>
<Td valIgn="top">
<fONT Size="2">
<p>Integer</P>
</FONt></td>
<tD VALign="top">
<fONT Size="2">
<p><tt class="monofont">int *</tt><i><tt clasS="monofont">r</tt></I>
</p>
</foNt></td>
</tR>
<tr>
<tD VALign="top">
<fONT Size="2">
<p><TT CLass="monofont">"l"</tT></P>
</FOnt></td>
<td valign="top">
<font size="2">
<P>Integer</p>
</fOnt></tD>
<td vaLign="top">
<FONT size="2">
<P><TT Class="monofont">long int *</TT><I><Tt claSS="monofont">r</TT></i>
</p>
</font></td>
</tr>
<tr>
<td valign="top">
<FonT sizE="2">
<p><tt cLass="monofont">"c"</TT></P>
</Font></tD>
<TD ValigN="top">
<FONt sizE="2">
<P>String of length 1</P>
</Font></td>
<td valign="top">
<font sizE="2">
<p><tT claSs="monofont">char *</tt><i><Tt clASS="monofont">r</Tt></i>
</p>
</fONT></Td>
</tr>
<tR>
<TD ValigN="top">
<FONt size="2">
<p><tt class="monofont">"f"</tt></p>
</font></Td>
<tD valIgn="top">
<foNt siZE="2">
<P>Float</P>
</font></TD>
<TD valiGN="top">
<FOnt siZE="2">
<P><Tt class="monofont">float *</tt><i><tt class="monofont">r</tt></i>
</p>
</FonT></td>
</tR>
<tr>
<td ValiGN="top">
<FOnt siZE="2">
<P><Tt claSS="monofont">"d"</TT></p>
</fonT></TD>
<Td valign="top">
<font size="2">
<p>Float</p>
</fonT></td>
<Td vaLign="top">
<fOnt sIZE="2">
<P><tt clASS="monofont">double *</Tt><i><tt CLASs="monofont">r</tt></i>
</P>
</FONt></td>
</tr>
<tr>
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