lib_scan.html

ST20 Embedded Toolset R2.0.5用于开发基于ST20芯片机顶盒软件的开发平台,2.0.5版本,国内找不到的.在国外论坛上花了N天才找到!

   %u       unsigned int *x        strtoul    10
  %hu       unsigned short *x      strtoul    10
  %lu       unsigned long *x       strtoul    10

   %x       unsigned int *x        strtoul    16
  %hx       unsigned short *x      strtoul    16
  %lx       unsigned long *x       strtoul    16

   %X       unsigned int *x        strtoul    16
  %hX       unsigned short *x      strtoul    16
  %lX       unsigned long *x       strtoul    16

 %[...]     char x[]
%l[...]     wchar_t x[]

   %%       <B>none</B></PRE>

<P>The scan conversion specifier (or
<A HREF="#scan set">scan set</A>) determines any behavior
not summarized in this table. In the following descriptions,
examples follow each of the scan conversion specifiers.
In each example, the function
<A HREF="stdio.html#sscanf"><CODE>sscanf</CODE></A>
matches the <B><CODE>bold</CODE></B> characters.</P>

<P>You write <B><A NAME="%c"><CODE>%c</CODE></A></B>
to store the matched input characters in
an array object. If you specify no field width <I>w,</I> then <I>w</I>
has the value one. The match does not skip leading
<A HREF="lib_prin.html#white space">white space</A>. Any
sequence of <I>w</I> characters matches the conversion pattern.</P>

<PRE>sscanf("<B>1</B>29E-2", "%c", &amp;c)             <B>stores '1'</B>
sscanf("<B>12</B>9E-2", "%2c", &amp;c[0])         <B>stores '1', '2'</B></PRE>

<P>For a
<A HREF="lib_file.html#wide stream">wide stream</A>,
conversion occurs as if by repeatedly calling
<A HREF="wchar.html#wcrtomb"><CODE>wcrtomb</CODE></A>,
beginning in the
<A HREF="charset.html#initial conversion state">
initial conversion state</A>.</P>

<PRE>swscanf(L"<B>1</B>29E-2", L"%c", &amp;c)          <B>stores '1'</B></PRE>

<P>You write <B><A NAME="%lc"><CODE>%lc</CODE></A></B>
to store the matched input characters in an array object,
with elements of type
<A HREF="stddef.html#wchar_t">wchar_t</A>.
If you specify no field width <I>w,</I> then <I>w</I>
has the value one. The match does not skip leading
<A HREF="lib_prin.html#white space">white space</A>. Any
sequence of <I>w</I> characters matches the conversion pattern. For a
<A HREF="lib_file.html#byte stream">byte stream</A>,
conversion occurs as if by repeatedly calling
<A HREF="wchar.html#wcrtomb"><CODE>mbrtowc</CODE></A>, beginning in the
<A HREF="charset.html#initial conversion state">
initial conversion state</A>.</P>

<PRE>sscanf("<B>1</B>29E-2", "%lc", &amp;c)            <B>stores L'1'</B>
sscanf("<B>12</B>9E-2", "%2lc", &amp;c)           <B>stores L'1', L'2'</B>
swscanf(L"<B>1</B>29E-2", L"%lc", &amp;c)         <B>stores L'1'</B></PRE>

<P>You write <B><A NAME="%d"><CODE>%d</CODE></A></B>,
<B><A NAME="%i"><CODE>%i</CODE></A></B>,
<B><A NAME="%o"><CODE>%o</CODE></A></B>,
<B><A NAME="%u"><CODE>%u</CODE></A></B>,
<B><A NAME="%x"><CODE>%x</CODE></A></B>, or
<B><A NAME="%X"><CODE>%X</CODE></A></B> to convert
the matched input characters as a signed integer
and store the result in an integer object.</P>

<PRE>sscanf("<B>129E</B>-2", "%o%d%x", &amp;i, &amp;j, &amp;k) <B>stores 10, 9, 14</B></PRE>

<P>You write
<B><A NAME="%e"><CODE>%e</CODE></A></B>,
<B><A NAME="%E"><CODE>%E</CODE></A></B>,
<B><A NAME="%f"><CODE>%f</CODE></A></B>,
<B><A NAME="%g"><CODE>%g</CODE></A></B>, or
<B><A NAME="%G"><CODE>%G</CODE></A></B>
to convert the matched input characters as a signed fraction, with
an optional exponent, and store the result in a floating-point object.</P>

<PRE>sscanf("<B>129E-2</B>", "%e", &amp;f)             <B>stores 1.29</B></PRE>

<P>You write <B><A NAME="%n"><CODE>%n</CODE></A></B>
to store the number of characters
matched (up to this point in the format) in an integer object. The
match does not skip leading
<A HREF="lib_prin.html#white space">white space</A>
and does not match any input characters.</P>

<PRE>sscanf("<B>12</B>9E-2", "12%n", &amp;i)           <B>stores 2</B></PRE>

<P>You write <B><A NAME="%p"><CODE>%p</CODE></A></B>
to convert the matched input characters as
an external representation of a <I>pointer to void</I> and store the
result in an object of type <I>pointer to void.</I> The input characters
must match the form generated by the
<A HREF="lib_prin.html#%p"><CODE>%p</CODE></A>
<A HREF="lib_prin.html#print conversion specification">
print conversion specification</A>.</P>

<PRE>sscanf("<B>129E</B>-2", "%p", &amp;p)             <B>stores, e.g. 0x129E</B></PRE>

<P>You write <B><A NAME="%s"><CODE>%s</CODE></A></B>
to store the matched input characters in
an array object, followed by a terminating null character. If you
do not specify a field width <I>w,</I> then <I>w</I> has a large value.
Any sequence of up to <I>w</I> non white-space characters matches
the conversion pattern.</P>

<PRE>sscanf("<B>129E-2</B>", "%s", &amp;s[0])          <B>stores "129E-2"</B></PRE>

<P>For a
<A HREF="lib_file.html#wide stream">wide stream</A>,
conversion occurs as if by repeatedly calling
<CODE>wcrtomb</CODE> beginning in the
<A HREF="charset.html#initial conversion state">
initial conversion state</A>.</P>

<PRE>swscanf(L"<B>129E-2</B>", L"%s", &amp;s[0])       <B>stores "129E-2"</B></PRE>

<P>You write <B><A NAME="%ls"><CODE>%ls</CODE></A></B>
to store the matched input characters in
an array object, with elements of type
<A HREF="stddef.html#wchar_t">wchar_t</A>,
followed by a terminating null wide character. If you
do not specify a field width <I>w,</I> then <I>w</I> has a large value.
Any sequence of up to <I>w</I> non white-space characters matches
the conversion pattern. For a
<A HREF="lib_file.html#byte stream">byte stream</A>,
conversion occurs as if by repeatedly calling
<A HREF="wchar.html#mbrtowc"><CODE>mbrtowc</CODE></A>,
beginning in the
<A HREF="charset.html#initial conversion state">
initial conversion state</A>.</P>

<PRE>sscanf("<B>129E-2</B>", "%ls", &amp;s[0])         <B>stores L"129E-2"</B>
swscanf(L"<B>129E-2</B>", L"%ls", &amp;s[0])      <B>stores L"129E-2"</B></PRE>

<P>You write <B><A NAME="%["><CODE>%[</CODE></A></B>
to store the matched input characters in
an array object, followed by a terminating null character. If you
do not specify a field width <I>w,</I> then <I>w</I> has a large value.
The match does not skip leading
<A HREF="lib_prin.html#white space">white space</A>.
A sequence of up to <I>w</I>
characters matches the conversion pattern in the
<B><A NAME="scan set">scan set</A></B> that follows.
To complete the scan set, you follow the left bracket
(<CODE>[</CODE>) in the conversion specification with a sequence
of zero or more <B>match</B> characters, terminated by a right bracket
(<B><CODE>]</CODE></B>).</P>

<P>If you do not write a caret (<B><CODE>^</CODE></B>)
immediately after the <CODE>[</CODE>, then each
input character must match <I>one</I> of the match
characters. Otherwise, each input character must not match <I>any</I>
of the match characters, which begin with the character following
the <CODE>^</CODE>. If you write a <B><CODE>]</CODE></B>
immediately after the <CODE>[</CODE> or <CODE>[^</CODE>,
then the <CODE>]</CODE> is the first match character, not
the terminating <CODE>]</CODE>. If you write a minus
(<B><CODE>-</CODE></B>) as other than the first or last match character,
an implementation can give it special meaning.
It usually indicates a range of characters, in conjunction with the
characters immediately preceding or following, as in
<CODE>0-9</CODE> for all the digits.)
You cannot specify a null match character.</P>

<PRE>sscanf("<B>12</B>9E-2", "%[54321]", &amp;s[0])     <B>stores "12"</B></PRE>

<P> For a <A HREF="lib_file.html#wide stream">wide stream</A>,
conversion occurs as if by repeatedly calling
<A HREF="wchar.html#wcrtomb"><CODE>wcrtomb</CODE></A>,
beginning in the
<A HREF="charset.html#initial conversion state">
initial conversion state</A>.</P>

<PRE>swscanf(L"<B>12</B>9E-2", L"%[54321]", &amp;s[0])  <B>stores "12"</B></PRE>

<P>You write <B><A NAME="%l["><CODE>%l[</CODE></A></B>
to store the matched input characters in
an array object, with elements of type
<A HREF="stddef.html#wchar_t">wchar_t</A>,
followed by a terminating null wide character. If you
do not specify a field width <I>w,</I> then <I>w</I> has a large value.
The match does not skip leading
<A HREF="lib_prin.html#white space">white space</A>.
A sequence of up to <I>w</I>
characters matches the conversion pattern in the
<A HREF="#scan set">scan set</A> that follows.

<P> For a <A HREF="lib_file.html#byte stream">byte stream</A>,
conversion occurs as if by repeatedly calling
<A HREF="wchar.html#mbrtowc"><CODE>mbrtowc</CODE></A>,
beginning in the
<A HREF="charset.html#initial conversion state">
initial conversion state</A>.</P>

<PRE>sscanf("<B>12</B>9E-2", "%l[54321]", &amp;s[0])    <B>stores L"12"</B>
swscanf(L"<B>12</B>9E-2", L"%l[54321]", &amp;s[0]) <B>stores L"12"</B></PRE>

<P>You write <B><A NAME="%%"><CODE>%%</CODE></A></B>
to match the percent character (<CODE>%</CODE>).
The function does not store a value.</P>

<PRE>sscanf("<B>%  0XA</B>", "%% %i", &amp;i)          <B>stores 10</B></PRE>

<HR>
<P>See also the
<B><A HREF="index.html#Table of Contents">Table of Contents</A></B> and the
<B><A HREF="_index.html">Index</A></B>.</P>

<P><I>
<A HREF="crit_pb.html">Copyright</A> &#169; 1989-2002
by P.J. Plauger and Jim Brodie. All rights reserved.</I></P>

<!--V4.01:1125--></BODY></HTML>