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  &lt;div class=&quot;section&quot; id=&quot;string-conversion-and-formatting&quot;&gt;
&lt;span id=&quot;string-conversion&quot;&gt;&lt;/span&gt;&lt;h1&gt;String conversion and formatting&lt;a class=&quot;headerlink&quot; href=&quot;#string-conversion-and-formatting&quot; title=&quot;Permalink to this headline&quot;&gt;¶&lt;/a&gt;&lt;/h1&gt;
&lt;p&gt;Functions for number conversion and formatted string output.&lt;/p&gt;
&lt;dl class=&quot;function&quot;&gt;
&lt;dt id=&quot;PyOS_snprintf&quot;&gt;
int &lt;tt class=&quot;descname&quot;&gt;PyOS_snprintf&lt;/tt&gt;&lt;big&gt;(&lt;/big&gt;char&lt;em&gt;&amp;nbsp;*str&lt;/em&gt;, size_t&lt;em&gt;&amp;nbsp;size&lt;/em&gt;, const char&lt;em&gt;&amp;nbsp;*format&lt;/em&gt;, ...&lt;big&gt;)&lt;/big&gt;&lt;a class=&quot;headerlink&quot; href=&quot;#PyOS_snprintf&quot; title=&quot;Permalink to this definition&quot;&gt;¶&lt;/a&gt;&lt;/dt&gt;
&lt;dd&gt;&lt;p&gt;Output not more than &lt;em&gt;size&lt;/em&gt; bytes to &lt;em&gt;str&lt;/em&gt; according to the format string
&lt;em&gt;format&lt;/em&gt; and the extra arguments. See the Unix man page &lt;em class=&quot;manpage&quot;&gt;snprintf(2)&lt;/em&gt;.&lt;/p&gt;
&lt;/dd&gt;&lt;/dl&gt;

&lt;dl class=&quot;function&quot;&gt;
&lt;dt id=&quot;PyOS_vsnprintf&quot;&gt;
int &lt;tt class=&quot;descname&quot;&gt;PyOS_vsnprintf&lt;/tt&gt;&lt;big&gt;(&lt;/big&gt;char&lt;em&gt;&amp;nbsp;*str&lt;/em&gt;, size_t&lt;em&gt;&amp;nbsp;size&lt;/em&gt;, const char&lt;em&gt;&amp;nbsp;*format&lt;/em&gt;, va_list&lt;em&gt;&amp;nbsp;va&lt;/em&gt;&lt;big&gt;)&lt;/big&gt;&lt;a class=&quot;headerlink&quot; href=&quot;#PyOS_vsnprintf&quot; title=&quot;Permalink to this definition&quot;&gt;¶&lt;/a&gt;&lt;/dt&gt;
&lt;dd&gt;&lt;p&gt;Output not more than &lt;em&gt;size&lt;/em&gt; bytes to &lt;em&gt;str&lt;/em&gt; according to the format string
&lt;em&gt;format&lt;/em&gt; and the variable argument list &lt;em&gt;va&lt;/em&gt;. Unix man page
&lt;em class=&quot;manpage&quot;&gt;vsnprintf(2)&lt;/em&gt;.&lt;/p&gt;
&lt;/dd&gt;&lt;/dl&gt;

&lt;p&gt;&lt;a class=&quot;reference internal&quot; href=&quot;#PyOS_snprintf&quot; title=&quot;PyOS_snprintf&quot;&gt;&lt;tt class=&quot;xref c c-func docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;PyOS_snprintf()&lt;/span&gt;&lt;/tt&gt;&lt;/a&gt; and &lt;a class=&quot;reference internal&quot; href=&quot;#PyOS_vsnprintf&quot; title=&quot;PyOS_vsnprintf&quot;&gt;&lt;tt class=&quot;xref c c-func docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;PyOS_vsnprintf()&lt;/span&gt;&lt;/tt&gt;&lt;/a&gt; wrap the Standard C library
functions &lt;tt class=&quot;xref c c-func docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;snprintf()&lt;/span&gt;&lt;/tt&gt; and &lt;tt class=&quot;xref c c-func docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;vsnprintf()&lt;/span&gt;&lt;/tt&gt;. Their purpose is to
guarantee consistent behavior in corner cases, which the Standard C functions do
not.&lt;/p&gt;
&lt;p&gt;The wrappers ensure that &lt;em&gt;str*[*size&lt;/em&gt;-1] is always &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'\0'&lt;/span&gt;&lt;/tt&gt; upon return. They
never write more than &lt;em&gt;size&lt;/em&gt; bytes (including the trailing &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'\0'&lt;/span&gt;&lt;/tt&gt; into str.
Both functions require that &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;str&lt;/span&gt; &lt;span class=&quot;pre&quot;&gt;!=&lt;/span&gt; &lt;span class=&quot;pre&quot;&gt;NULL&lt;/span&gt;&lt;/tt&gt;, &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;size&lt;/span&gt; &lt;span class=&quot;pre&quot;&gt;&amp;gt;&lt;/span&gt; &lt;span class=&quot;pre&quot;&gt;0&lt;/span&gt;&lt;/tt&gt; and &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;format&lt;/span&gt; &lt;span class=&quot;pre&quot;&gt;!=&lt;/span&gt;
&lt;span class=&quot;pre&quot;&gt;NULL&lt;/span&gt;&lt;/tt&gt;.&lt;/p&gt;
&lt;p&gt;If the platform doesn&amp;#8217;t have &lt;tt class=&quot;xref c c-func docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;vsnprintf()&lt;/span&gt;&lt;/tt&gt; and the buffer size needed to
avoid truncation exceeds &lt;em&gt;size&lt;/em&gt; by more than 512 bytes, Python aborts with a
&lt;em&gt;Py_FatalError&lt;/em&gt;.&lt;/p&gt;
&lt;p&gt;The return value (&lt;em&gt;rv&lt;/em&gt;) for these functions should be interpreted as follows:&lt;/p&gt;
&lt;ul class=&quot;simple&quot;&gt;
&lt;li&gt;When &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;0&lt;/span&gt; &lt;span class=&quot;pre&quot;&gt;&amp;lt;=&lt;/span&gt; &lt;span class=&quot;pre&quot;&gt;rv&lt;/span&gt; &lt;span class=&quot;pre&quot;&gt;&amp;lt;&lt;/span&gt; &lt;span class=&quot;pre&quot;&gt;size&lt;/span&gt;&lt;/tt&gt;, the output conversion was successful and &lt;em&gt;rv&lt;/em&gt;
characters were written to &lt;em&gt;str&lt;/em&gt; (excluding the trailing &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'\0'&lt;/span&gt;&lt;/tt&gt; byte at
&lt;em&gt;str*[*rv&lt;/em&gt;]).&lt;/li&gt;
&lt;li&gt;When &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;rv&lt;/span&gt; &lt;span class=&quot;pre&quot;&gt;&amp;gt;=&lt;/span&gt; &lt;span class=&quot;pre&quot;&gt;size&lt;/span&gt;&lt;/tt&gt;, the output conversion was truncated and a buffer with
&lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;rv&lt;/span&gt; &lt;span class=&quot;pre&quot;&gt;+&lt;/span&gt; &lt;span class=&quot;pre&quot;&gt;1&lt;/span&gt;&lt;/tt&gt; bytes would have been needed to succeed. &lt;em&gt;str*[*size&lt;/em&gt;-1] is &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'\0'&lt;/span&gt;&lt;/tt&gt;
in this case.&lt;/li&gt;
&lt;li&gt;When &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;rv&lt;/span&gt; &lt;span class=&quot;pre&quot;&gt;&amp;lt;&lt;/span&gt; &lt;span class=&quot;pre&quot;&gt;0&lt;/span&gt;&lt;/tt&gt;, &amp;#8220;something bad happened.&amp;#8221; &lt;em&gt;str*[*size&lt;/em&gt;-1] is &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'\0'&lt;/span&gt;&lt;/tt&gt; in
this case too, but the rest of &lt;em&gt;str&lt;/em&gt; is undefined. The exact cause of the error
depends on the underlying platform.&lt;/li&gt;
&lt;/ul&gt;
&lt;p&gt;The following functions provide locale-independent string to number conversions.&lt;/p&gt;
&lt;dl class=&quot;function&quot;&gt;
&lt;dt id=&quot;PyOS_string_to_double&quot;&gt;
double &lt;tt class=&quot;descname&quot;&gt;PyOS_string_to_double&lt;/tt&gt;&lt;big&gt;(&lt;/big&gt;const char&lt;em&gt;&amp;nbsp;*s&lt;/em&gt;, char&lt;em&gt;&amp;nbsp;**endptr&lt;/em&gt;, &lt;a class=&quot;reference internal&quot; href=&quot;structures.html#PyObject&quot; title=&quot;PyObject&quot;&gt;PyObject&lt;/a&gt;&lt;em&gt;&amp;nbsp;*overflow_exception&lt;/em&gt;&lt;big&gt;)&lt;/big&gt;&lt;a class=&quot;headerlink&quot; href=&quot;#PyOS_string_to_double&quot; title=&quot;Permalink to this definition&quot;&gt;¶&lt;/a&gt;&lt;/dt&gt;
&lt;dd&gt;&lt;p&gt;Convert a string &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;s&lt;/span&gt;&lt;/tt&gt; to a &lt;tt class=&quot;xref c c-type docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;double&lt;/span&gt;&lt;/tt&gt;, raising a Python
exception on failure.  The set of accepted strings corresponds to
the set of strings accepted by Python&amp;#8217;s &lt;a class=&quot;reference internal&quot; href=&quot;../library/functions.html#float&quot; title=&quot;float&quot;&gt;&lt;tt class=&quot;xref py py-func docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;float()&lt;/span&gt;&lt;/tt&gt;&lt;/a&gt; constructor,
except that &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;s&lt;/span&gt;&lt;/tt&gt; must not have leading or trailing whitespace.
The conversion is independent of the current locale.&lt;/p&gt;
&lt;p&gt;If &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;endptr&lt;/span&gt;&lt;/tt&gt; is &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;NULL&lt;/span&gt;&lt;/tt&gt;, convert the whole string.  Raise
ValueError and return &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;-1.0&lt;/span&gt;&lt;/tt&gt; if the string is not a valid
representation of a floating-point number.&lt;/p&gt;
&lt;p&gt;If endptr is not &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;NULL&lt;/span&gt;&lt;/tt&gt;, convert as much of the string as
possible and set &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;*endptr&lt;/span&gt;&lt;/tt&gt; to point to the first unconverted
character.  If no initial segment of the string is the valid
representation of a floating-point number, set &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;*endptr&lt;/span&gt;&lt;/tt&gt; to point
to the beginning of the string, raise ValueError, and return
&lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;-1.0&lt;/span&gt;&lt;/tt&gt;.&lt;/p&gt;
&lt;p&gt;If &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;s&lt;/span&gt;&lt;/tt&gt; represents a value that is too large to store in a float
(for example, &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;&amp;quot;1e500&amp;quot;&lt;/span&gt;&lt;/tt&gt; is such a string on many platforms) then
if &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;overflow_exception&lt;/span&gt;&lt;/tt&gt; is &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;NULL&lt;/span&gt;&lt;/tt&gt; return &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;Py_HUGE_VAL&lt;/span&gt;&lt;/tt&gt; (with
an appropriate sign) and don&amp;#8217;t set any exception.  Otherwise,
&lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;overflow_exception&lt;/span&gt;&lt;/tt&gt; must point to a Python exception object;
raise that exception and return &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;-1.0&lt;/span&gt;&lt;/tt&gt;.  In both cases, set
&lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;*endptr&lt;/span&gt;&lt;/tt&gt; to point to the first character after the converted value.&lt;/p&gt;
&lt;p&gt;If any other error occurs during the conversion (for example an
out-of-memory error), set the appropriate Python exception and
return &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;-1.0&lt;/span&gt;&lt;/tt&gt;.&lt;/p&gt;
&lt;p class=&quot;versionadded&quot;&gt;
&lt;span class=&quot;versionmodified&quot;&gt;New in version 2.7.&lt;/span&gt;&lt;/p&gt;
&lt;/dd&gt;&lt;/dl&gt;

&lt;dl class=&quot;function&quot;&gt;
&lt;dt id=&quot;PyOS_ascii_strtod&quot;&gt;
double &lt;tt class=&quot;descname&quot;&gt;PyOS_ascii_strtod&lt;/tt&gt;&lt;big&gt;(&lt;/big&gt;const char&lt;em&gt;&amp;nbsp;*nptr&lt;/em&gt;, char&lt;em&gt;&amp;nbsp;**endptr&lt;/em&gt;&lt;big&gt;)&lt;/big&gt;&lt;a class=&quot;headerlink&quot; href=&quot;#PyOS_ascii_strtod&quot; title=&quot;Permalink to this definition&quot;&gt;¶&lt;/a&gt;&lt;/dt&gt;
&lt;dd&gt;&lt;p&gt;Convert a string to a &lt;tt class=&quot;xref c c-type docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;double&lt;/span&gt;&lt;/tt&gt;. This function behaves like the Standard C
function &lt;tt class=&quot;xref c c-func docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;strtod()&lt;/span&gt;&lt;/tt&gt; does in the C locale. It does this without changing the
current locale, since that would not be thread-safe.&lt;/p&gt;
&lt;p&gt;&lt;a class=&quot;reference internal&quot; href=&quot;#PyOS_ascii_strtod&quot; title=&quot;PyOS_ascii_strtod&quot;&gt;&lt;tt class=&quot;xref c c-func docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;PyOS_ascii_strtod()&lt;/span&gt;&lt;/tt&gt;&lt;/a&gt; should typically be used for reading configuration
files or other non-user input that should be locale independent.&lt;/p&gt;
&lt;p&gt;See the Unix man page &lt;em class=&quot;manpage&quot;&gt;strtod(2)&lt;/em&gt; for details.&lt;/p&gt;
&lt;p class=&quot;versionadded&quot;&gt;
&lt;span class=&quot;versionmodified&quot;&gt;New in version 2.4.&lt;/span&gt;&lt;/p&gt;
&lt;p class=&quot;deprecated&quot;&gt;
&lt;span class=&quot;versionmodified&quot;&gt;Deprecated since version 2.7: &lt;/span&gt;Use &lt;a class=&quot;reference internal&quot; href=&quot;#PyOS_string_to_double&quot; title=&quot;PyOS_string_to_double&quot;&gt;&lt;tt class=&quot;xref c c-func docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;PyOS_string_to_double()&lt;/span&gt;&lt;/tt&gt;&lt;/a&gt; instead.&lt;/p&gt;
&lt;/dd&gt;&lt;/dl&gt;

&lt;dl class=&quot;function&quot;&gt;
&lt;dt id=&quot;PyOS_ascii_formatd&quot;&gt;
char* &lt;tt class=&quot;descname&quot;&gt;PyOS_ascii_formatd&lt;/tt&gt;&lt;big&gt;(&lt;/big&gt;char&lt;em&gt;&amp;nbsp;*buffer&lt;/em&gt;, size_t&lt;em&gt;&amp;nbsp;buf_len&lt;/em&gt;, const char&lt;em&gt;&amp;nbsp;*format&lt;/em&gt;, double&lt;em&gt;&amp;nbsp;d&lt;/em&gt;&lt;big&gt;)&lt;/big&gt;&lt;a class=&quot;headerlink&quot; href=&quot;#PyOS_ascii_formatd&quot; title=&quot;Permalink to this definition&quot;&gt;¶&lt;/a&gt;&lt;/dt&gt;
&lt;dd&gt;&lt;p&gt;Convert a &lt;tt class=&quot;xref c c-type docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;double&lt;/span&gt;&lt;/tt&gt; to a string using the &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'.'&lt;/span&gt;&lt;/tt&gt; as the decimal
separator. &lt;em&gt;format&lt;/em&gt; is a &lt;tt class=&quot;xref c c-func docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;printf()&lt;/span&gt;&lt;/tt&gt;-style format string specifying the
number format. Allowed conversion characters are &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'e'&lt;/span&gt;&lt;/tt&gt;, &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'E'&lt;/span&gt;&lt;/tt&gt;, &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'f'&lt;/span&gt;&lt;/tt&gt;,
&lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'F'&lt;/span&gt;&lt;/tt&gt;, &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'g'&lt;/span&gt;&lt;/tt&gt; and &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'G'&lt;/span&gt;&lt;/tt&gt;.&lt;/p&gt;
&lt;p&gt;The return value is a pointer to &lt;em&gt;buffer&lt;/em&gt; with the converted string or NULL if
the conversion failed.&lt;/p&gt;
&lt;p class=&quot;versionadded&quot;&gt;
&lt;span class=&quot;versionmodified&quot;&gt;New in version 2.4.&lt;/span&gt;&lt;/p&gt;
&lt;p class=&quot;deprecated&quot;&gt;
&lt;span class=&quot;versionmodified&quot;&gt;Deprecated since version 2.7: &lt;/span&gt;This function is removed in Python 2.7 and 3.1.  Use &lt;tt class=&quot;xref py py-func docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;PyOS_double_to_string()&lt;/span&gt;&lt;/tt&gt;
instead.&lt;/p&gt;
&lt;/dd&gt;&lt;/dl&gt;

&lt;dl class=&quot;function&quot;&gt;
&lt;dt id=&quot;PyOS_double_to_string&quot;&gt;
char* &lt;tt class=&quot;descname&quot;&gt;PyOS_double_to_string&lt;/tt&gt;&lt;big&gt;(&lt;/big&gt;double&lt;em&gt;&amp;nbsp;val&lt;/em&gt;, char&lt;em&gt;&amp;nbsp;format_code&lt;/em&gt;, int&lt;em&gt;&amp;nbsp;precision&lt;/em&gt;, int&lt;em&gt;&amp;nbsp;flags&lt;/em&gt;, int&lt;em&gt;&amp;nbsp;*ptype&lt;/em&gt;&lt;big&gt;)&lt;/big&gt;&lt;a class=&quot;headerlink&quot; href=&quot;#PyOS_double_to_string&quot; title=&quot;Permalink to this definition&quot;&gt;¶&lt;/a&gt;&lt;/dt&gt;
&lt;dd&gt;&lt;p&gt;Convert a &lt;tt class=&quot;xref c c-type docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;double&lt;/span&gt;&lt;/tt&gt; &lt;em&gt;val&lt;/em&gt; to a string using supplied
&lt;em&gt;format_code&lt;/em&gt;, &lt;em&gt;precision&lt;/em&gt;, and &lt;em&gt;flags&lt;/em&gt;.&lt;/p&gt;
&lt;p&gt;&lt;em&gt;format_code&lt;/em&gt; must be one of &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'e'&lt;/span&gt;&lt;/tt&gt;, &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'E'&lt;/span&gt;&lt;/tt&gt;, &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'f'&lt;/span&gt;&lt;/tt&gt;, &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'F'&lt;/span&gt;&lt;/tt&gt;,
&lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'g'&lt;/span&gt;&lt;/tt&gt;, &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'G'&lt;/span&gt;&lt;/tt&gt; or &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'r'&lt;/span&gt;&lt;/tt&gt;.  For &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'r'&lt;/span&gt;&lt;/tt&gt;, the supplied &lt;em&gt;precision&lt;/em&gt;
must be 0 and is ignored.  The &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'r'&lt;/span&gt;&lt;/tt&gt; format code specifies the
standard &lt;a class=&quot;reference internal&quot; href=&quot;../library/repr.html#module-repr&quot; title=&quot;repr: Alternate repr() implementation with size limits.&quot;&gt;&lt;tt class=&quot;xref py py-func docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;repr()&lt;/span&gt;&lt;/tt&gt;&lt;/a&gt; format.&lt;/p&gt;
&lt;p&gt;&lt;em&gt;flags&lt;/em&gt; can be zero or more of the values &lt;em&gt;Py_DTSF_SIGN&lt;/em&gt;,
&lt;em&gt;Py_DTSF_ADD_DOT_0&lt;/em&gt;, or &lt;em&gt;Py_DTSF_ALT&lt;/em&gt;, or-ed together:&lt;/p&gt;
&lt;ul class=&quot;simple&quot;&gt;
&lt;li&gt;&lt;em&gt;Py_DTSF_SIGN&lt;/em&gt; means to always precede the returned string with a sign
character, even if &lt;em&gt;val&lt;/em&gt; is non-negative.&lt;/li&gt;
&lt;li&gt;&lt;em&gt;Py_DTSF_ADD_DOT_0&lt;/em&gt; means to ensure that the returned string will not look
like an integer.&lt;/li&gt;
&lt;li&gt;&lt;em&gt;Py_DTSF_ALT&lt;/em&gt; means to apply &amp;#8220;alternate&amp;#8221; formatting rules.  See the
documentation for the &lt;a class=&quot;reference internal&quot; href=&quot;#PyOS_snprintf&quot; title=&quot;PyOS_snprintf&quot;&gt;&lt;tt class=&quot;xref c c-func docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;PyOS_snprintf()&lt;/span&gt;&lt;/tt&gt;&lt;/a&gt; &lt;tt class=&quot;docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;'#'&lt;/span&gt;&lt;/tt&gt; specifier for
details.&lt;/li&gt;
&lt;/ul&gt;
&lt;p&gt;If &lt;em&gt;ptype&lt;/em&gt; is non-NULL, then the value it points to will be set to one of
&lt;em&gt;Py_DTST_FINITE&lt;/em&gt;, &lt;em&gt;Py_DTST_INFINITE&lt;/em&gt;, or &lt;em&gt;Py_DTST_NAN&lt;/em&gt;, signifying that
&lt;em&gt;val&lt;/em&gt; is a finite number, an infinite number, or not a number, respectively.&lt;/p&gt;
&lt;p&gt;The return value is a pointer to &lt;em&gt;buffer&lt;/em&gt; with the converted string or
&lt;em&gt;NULL&lt;/em&gt; if the conversion failed. The caller is responsible for freeing the
returned string by calling &lt;a class=&quot;reference internal&quot; href=&quot;memory.html#PyMem_Free&quot; title=&quot;PyMem_Free&quot;&gt;&lt;tt class=&quot;xref c c-func docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;PyMem_Free()&lt;/span&gt;&lt;/tt&gt;&lt;/a&gt;.&lt;/p&gt;
&lt;p class=&quot;versionadded&quot;&gt;
&lt;span class=&quot;versionmodified&quot;&gt;New in version 2.7.&lt;/span&gt;&lt;/p&gt;
&lt;/dd&gt;&lt;/dl&gt;

&lt;dl class=&quot;function&quot;&gt;
&lt;dt id=&quot;PyOS_ascii_atof&quot;&gt;
double &lt;tt class=&quot;descname&quot;&gt;PyOS_ascii_atof&lt;/tt&gt;&lt;big&gt;(&lt;/big&gt;const char&lt;em&gt;&amp;nbsp;*nptr&lt;/em&gt;&lt;big&gt;)&lt;/big&gt;&lt;a class=&quot;headerlink&quot; href=&quot;#PyOS_ascii_atof&quot; title=&quot;Permalink to this definition&quot;&gt;¶&lt;/a&gt;&lt;/dt&gt;
&lt;dd&gt;&lt;p&gt;Convert a string to a &lt;tt class=&quot;xref c c-type docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;double&lt;/span&gt;&lt;/tt&gt; in a locale-independent way.&lt;/p&gt;
&lt;p&gt;See the Unix man page &lt;em class=&quot;manpage&quot;&gt;atof(2)&lt;/em&gt; for details.&lt;/p&gt;
&lt;p class=&quot;versionadded&quot;&gt;
&lt;span class=&quot;versionmodified&quot;&gt;New in version 2.4.&lt;/span&gt;&lt;/p&gt;
&lt;p class=&quot;deprecated&quot;&gt;
&lt;span class=&quot;versionmodified&quot;&gt;Deprecated since version 3.1: &lt;/span&gt;Use &lt;a class=&quot;reference internal&quot; href=&quot;#PyOS_string_to_double&quot; title=&quot;PyOS_string_to_double&quot;&gt;&lt;tt class=&quot;xref c c-func docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;PyOS_string_to_double()&lt;/span&gt;&lt;/tt&gt;&lt;/a&gt; instead.&lt;/p&gt;
&lt;/dd&gt;&lt;/dl&gt;

&lt;dl class=&quot;function&quot;&gt;
&lt;dt id=&quot;PyOS_stricmp&quot;&gt;
char* &lt;tt class=&quot;descname&quot;&gt;PyOS_stricmp&lt;/tt&gt;&lt;big&gt;(&lt;/big&gt;char&lt;em&gt;&amp;nbsp;*s1&lt;/em&gt;, char&lt;em&gt;&amp;nbsp;*s2&lt;/em&gt;&lt;big&gt;)&lt;/big&gt;&lt;a class=&quot;headerlink&quot; href=&quot;#PyOS_stricmp&quot; title=&quot;Permalink to this definition&quot;&gt;¶&lt;/a&gt;&lt;/dt&gt;
&lt;dd&gt;&lt;p&gt;Case insensitive comparison of strings. The function works almost
identically to &lt;tt class=&quot;xref c c-func docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;strcmp()&lt;/span&gt;&lt;/tt&gt; except that it ignores the case.&lt;/p&gt;
&lt;p class=&quot;versionadded&quot;&gt;
&lt;span class=&quot;versionmodified&quot;&gt;New in version 2.6.&lt;/span&gt;&lt;/p&gt;
&lt;/dd&gt;&lt;/dl&gt;

&lt;dl class=&quot;function&quot;&gt;
&lt;dt id=&quot;PyOS_strnicmp&quot;&gt;
char* &lt;tt class=&quot;descname&quot;&gt;PyOS_strnicmp&lt;/tt&gt;&lt;big&gt;(&lt;/big&gt;char&lt;em&gt;&amp;nbsp;*s1&lt;/em&gt;, char&lt;em&gt;&amp;nbsp;*s2&lt;/em&gt;, Py_ssize_t &lt;em&gt;&amp;nbsp;size&lt;/em&gt;&lt;big&gt;)&lt;/big&gt;&lt;a class=&quot;headerlink&quot; href=&quot;#PyOS_strnicmp&quot; title=&quot;Permalink to this definition&quot;&gt;¶&lt;/a&gt;&lt;/dt&gt;
&lt;dd&gt;&lt;p&gt;Case insensitive comparison of strings. The function works almost
identically to &lt;tt class=&quot;xref c c-func docutils literal&quot;&gt;&lt;span class=&quot;pre&quot;&gt;strncmp()&lt;/span&gt;&lt;/tt&gt; except that it ignores the case.&lt;/p&gt;
&lt;p class=&quot;versionadded&quot;&gt;
&lt;span class=&quot;versionmodified&quot;&gt;New in version 2.6.&lt;/span&gt;&lt;/p&gt;
&lt;/dd&gt;&lt;/dl&gt;

&lt;/div&gt;


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