ios.html

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<LI><CODE><A HREF="#ios_base::flags">flags</A>()</CODE> returns
<CODE><A HREF="#ios_base::skipws">skipws</A> |
<A HREF="#ios_base::dec">dec</A></CODE></LI>

<LI><CODE><A HREF="#ios_base::width">width</A>()</CODE> returns zero</LI>

<LI><CODE><A HREF="#ios_base::precision">precision</A>()</CODE>
returns 6</LI>

<LI><CODE><A HREF="#ios::fill">fill</A>()</CODE> returns the
space character</LI>

<LI><CODE><A HREF="#ios_base::getloc">getloc</A>()</CODE> returns
<CODE><A HREF="#locale">locale</A>()</CODE>.</LI>

<LI><CODE><A HREF="#ios_base::iword">iword</A></CODE> returns zero and
<CODE><A HREF="#ios_base::pword">pword</A></CODE> returns a null
pointer for all argument value</LI>
</UL>

<H3><A NAME="ios::int_type"><CODE>ios::int_type</CODE></A></H3>

<PRE>typedef int <B>int_type</B>;</PRE>

<P>The type is a synonym for <I>int.</I></P>

<H3><A NAME="ios::narrow"><CODE>ios::narrow</CODE></A></H3>

<PRE>char <B>narrow</B>(char_type ch, char dflt);</PRE>

<P>The member function returns
<CODE>ch</CODE>.</P>

<H3><A NAME="ios::off_type"><CODE>ios::off_type</CODE></A></H3>

<PRE>typedef streamoff <B>off_type</B>;</PRE>

<P>The type is a synonym for
<CODE><A HREF="#streamoff">streamoff</A></CODE>.</P>

<H3><A NAME="ios::operator void *"><CODE>ios::operator void *</CODE></A></H3>

<PRE><B>operator void *</B>() const;</PRE>

<P>The operator returns a null pointer only if
<CODE><A HREF="#ios::fail">fail</A>()</CODE>.</P>

<H3><A NAME="ios::operator!"><CODE>ios::operator!</CODE></A></H3>

<PRE>bool <B>operator!</B>() const;</PRE>

<P>The operator returns
<CODE><A HREF="#ios::fail">fail</A>()</CODE>.</P>

<H3><A NAME="ios::pos_type"><CODE>ios::pos_type</CODE></A></H3>

<PRE>typedef streampos <B>pos_type</B>;</PRE>

<P>The type is a synonym for
<CODE><A HREF="#streampos">streampos</A></CODE>.</P>

<H3><A NAME="ios::rdbuf"><CODE>ios::rdbuf</CODE></A></H3>

<PRE>streambuf *<B>rdbuf</B>() const;
streambuf *<B>rdbuf</B>(streambuf *strbuf);</PRE>

<P>The first member function returns the stored
<A HREF="#stream buffer pointer">stream buffer pointer</A>.</P>
<P>The second member function stores <CODE>strbuf</CODE> in the stored
<A HREF="#stream buffer pointer">stream buffer pointer</A>
and returns the previously stored value.</P>

<H3><A NAME="ios::rdstate"><CODE>ios::rdstate</CODE></A></H3>

<PRE>iostate <B>rdstate</B>() const;</PRE>

<P>The member function returns the stored
<A HREF="#stream state information">stream state information</A>.</P>

<H3><A NAME="ios::setstate"><CODE>ios::setstate</CODE></A></H3>

<PRE>void <B>setstate</B>(iostate state);</PRE>

<P>The member function effectively calls
<CODE><A HREF="#ios::clear">clear</A>(state |
<A HREF="#ios::rdstate">rdstate</A>())</CODE>.</P>

<H3><A NAME="ios::tie"><CODE>ios::tie</CODE></A></H3>

<PRE>ostream *<B>tie</B>() const;
ostream *<B>tie</B>(ostream *newtie);</PRE>

<P>The first member function returns the stored
<A HREF="#tie pointer">tie pointer</A>. The second member function
stores <CODE>newtie</CODE> in the tie pointer and returns its previous
stored value.</P>

<H3><A NAME="ios::traits_type"><CODE>ios::traits_type</CODE></A></H3>

<PRE>typedef char_traits <B>traits_type</B>;</PRE>

<P>The type is a synonym for
<CODE><A HREF="string2.html#char_traits">char_traits</A></CODE>.</P>

<H3><A NAME="ios::widen"><CODE>ios::widen</CODE></A></H3>

<PRE>char_type <B>widen</B>(char ch);</PRE>

<P>The member function returns
<CODE>ch</CODE>.</P>

<H2><A NAME="boolalpha"><CODE>boolalpha</CODE></A></H2>

<PRE>ios_base&amp; <B>boolalpha</B>(ios_base&amp; iosbase);</PRE>

<P>The manipulator effectively calls
<CODE>iosbase.<A HREF="#ios_base::setf">setf</A>(ios_base::
<A HREF="#ios_base::boolalpha">boolalpha</A>)</CODE>, then returns
<CODE>iosbase</CODE>.</P>

<H2><A NAME="dec"><CODE>dec</CODE></A></H2>

<PRE>ios_base&amp; <B>dec</B>(ios_base&amp; iosbase);</PRE>

<P>The manipulator effectively calls
<CODE>iosbase.<A HREF="#ios_base::setf">setf</A>(ios_base::
<A HREF="#ios_base::dec">dec</A>, ios_base::
<A HREF="#ios_base::basefield">basefield</A>)</CODE>, then returns
<CODE>iosbase</CODE>.</P>

<H2><A NAME="fixed"><CODE>fixed</CODE></A></H2>

<PRE>ios_base&amp; <B>fixed</B>(ios_base&amp; iosbase);</PRE>

<P>The manipulator effectively calls
<CODE>iosbase.<A HREF="#ios_base::setf">setf</A>(ios_base::
<A HREF="#ios_base::fixed">fixed</A>, ios_base::
<A HREF="#ios_base::floatfield">floatfield</A>)</CODE>, then returns
<CODE>iosbase</CODE>.</P>

<H2><A NAME="fpos"><CODE>fpos</CODE></A></H2>

<PRE>class <B>fpos</B> {
public:
    typedef mbstate_t St;
    <B><A HREF="#fpos::fpos">fpos</A></B>(streamoff off);
    <B><A HREF="#fpos::fpos">fpos</A></B>(St state, fpos_t filepos);
    St <B><A HREF="#fpos::state">state</A></B>() const;
    void <B><A HREF="#fpos::state">state</A></B>(St state);
    <B><A HREF="#fpos::operator streamoff">operator streamoff</A></B>() const;
    streamoff <B><A HREF="#fpos::operator-">operator-</A></B>(const fpos&amp; right) const;
    fpos&amp; <B><A HREF="#fpos::operator+=">operator+=</A></B>(streamoff off);
    fpos&amp; <B><A HREF="#fpos::operator-=">operator-=</A></B>(streamoff off);
    fpos <B><A HREF="#fpos::operator+">operator+</A></B>(streamoff off) const;
    fpos <B><A HREF="#fpos::operator-">operator-</A></B>(streamoff off) const;
    bool <B><A HREF="#fpos::operator==">operator==</A></B>(const fpos&amp; right) const;
    bool <B><A HREF="#fpos::operator!=">operator!=</A></B>(const fpos&amp; right) const;
    };</PRE>

<P>The class describes an object
that can store all the information needed to restore an arbitrary
<A HREF="lib_file.html#file-position indicator">file-position indicator</A>
within any stream. An object of class <CODE>fpos</CODE> effectively
stores at least two member objects:</P>

<UL>
<LI>a byte offset, of type
<CODE><A HREF="#streamoff">streamoff</A></CODE></LI>

<LI>a conversion state, for use by an object of class <CODE>filebuf</CODE>,
of type <B><CODE>St</CODE></B>, which is an unofficial synonym for
<CODE><A HREF="#mbstate_t">mbstate_t</A></CODE></LI>
</UL>

<P>It can also store an arbitrary file position, for use by an object of class
<CODE><A HREF="fstream.html#filebuf">filebuf</A></CODE>,
of type <CODE><A HREF="stdio.html#fpos_t">fpos_t</A></CODE>.
For an environment with limited file size, however,
<CODE>streamoff</CODE> and <CODE>fpos_t</CODE> may sometimes
be used interchangeably. So the number of
member objects stored may vary.</P>

<H3><A NAME="fpos::fpos"><CODE>fpos::fpos</CODE></A></H3>

<PRE><B>fpos</B>(streamoff off);
<B>fpos</B>(St state, fpos_t filepos);</PRE>

<P>The first constructor stores the offset
<CODE>off</CODE>,
relative to the beginning of file.
If <CODE>off</CODE> is -1,
the resulting object represents an invalid stream position.</P>

<P>The second constructor stores the object <CODE>state</CODE>
and a file position determined by <CODE>filepos</CODE>.</P>

<H3><A NAME="fpos::operator!="><CODE>fpos::operator!=</CODE></A></H3>

<PRE>bool <B>operator!=</B>(const fpos&amp; right) const;</PRE>

<P>The member function returns <CODE>!(*this == right)</CODE>.</P>

<H3><A NAME="fpos::operator+"><CODE>fpos::operator+</CODE></A></H3>

<PRE>fpos <B>operator+</B>(streamoff off) const;</PRE>

<P>The member function returns <CODE>fpos(*this) += off</CODE>.</P>

<H3><A NAME="fpos::operator+="><CODE>fpos::operator+=</CODE></A></H3>

<PRE>fpos&amp; <B>operator+=</B>(streamoff off);</PRE>

<P>The member function adds <CODE>off</CODE> to the stored offset member object,
then returns <CODE>*this</CODE>. For positioning within a file, the
result is generally valid only for
<A HREF="lib_file.html#binary stream">binary streams</A>.</P>

<H3><A NAME="fpos::operator-"><CODE>fpos::operator-</CODE></A></H3>

<PRE>streamoff <B>operator-</B>(const fpos&amp; right) const;
fpos <B>operator-</B>(streamoff off) const;</PRE>

<P>The first member function returns <CODE>(streamoff)*this - (streamoff)right</CODE>.
The second member function returns <CODE>fpos(*this) -= off</CODE>.</P>

<H3><A NAME="fpos::operator-="><CODE>fpos::operator-=</CODE></A></H3>

<PRE>fpos&amp; <B>operator-=</B>(streamoff off);</PRE>

<P>The member function returns <CODE>fpos(*this) -= off</CODE>.
For positioning within a file, the result is generally valid only for
<A HREF="lib_file.html#binary stream">binary streams</A>.</P>

<H3><A NAME="fpos::operator=="><CODE>fpos::operator==</CODE></A></H3>

<PRE>bool <B>operator==</B>(const fpos&amp; right) const;</PRE>

<P>The member function returns <CODE>(streamoff)*this == (streamoff)right</CODE>.</P>

<H3><A NAME="fpos::operator streamoff"><CODE>fpos::operator streamoff</CODE></A></H3>

<PRE><B>operator streamoff</B>() const;</PRE>

<P>The member function returns the stored offset member object,
plus any additional offset stored as part of the <CODE>fpos_t</CODE> member object.</P>

<H3><A NAME="fpos::state"><CODE>fpos::state</CODE></A></H3>

<PRE>St <B><A HREF="#fpos::state">state</A></B>() const;
void <B><A HREF="#fpos::state">state</A></B>(St state);</PRE>

<P>The first member function returns the value stored in the
<CODE>St</CODE> member object. The second member function
stores <CODE>state</CODE> in the <CODE>St</CODE> member object.</P>

<H2><A NAME="hex"><CODE>hex</CODE></A></H2>

<PRE>ios_base&amp; <B>hex</B>(ios_base&amp; iosbase);</PRE>

<P>The manipulator effectively calls
<CODE>iosbase.<A HREF="#ios_base::setf">setf</A>(ios_base::
<A HREF="#ios_base::hex">hex</A>, ios_base::
<A HREF="#ios_base::basefield">basefield</A>)</CODE>, then returns
<CODE>iosbase</CODE>.</P>

<H2><A NAME="internal"><CODE>internal</CODE></A></H2>

<PRE>ios_base&amp; <B>internal</B>(ios_base&amp; iosbase);</PRE>

<P>The manipulator effectively calls
<CODE>iosbase.<A HREF="#ios_base::setf">setf</A>(ios_base::
<A HREF="#ios_base::internal">internal</A>, ios_base::
<A HREF="#ios_base::adjustfield">adjustfield</A>)</CODE>, then returns
<CODE>iosbase</CODE>.</P>


<H2><A NAME="ios_base"><CODE>ios_base</CODE></A></H2>

<HR>
<P><B><CODE><A HREF="#ios_base::event">event</A>
&#183; <A HREF="#ios_base::event_callback">event_callback</A>
&#183; <A HREF="#ios_base::failure">failure</A>
&#183; <A HREF="#ios_base::flags">flags</A>
&#183; <A HREF="#ios_base::fmtflags">fmtflags</A>
&#183; <A HREF="#ios_base::getloc">getloc</A>
&#183; <A HREF="#ios_base::imbue">imbue</A>
&#183; <A HREF="#ios_base::Init">Init</A>
&#183; <A HREF="#ios_base::ios_base">ios_base</A>
&#183; <A HREF="#ios_base::iostate">iostate</A>
&#183; <A HREF="#ios_base::iword">iword</A>
&#183; <A HREF="#ios_base::openmode">openmode</A>
&#183; <A HREF="#ios_base::operator=">operator=</A>
&#183; <A HREF="#ios_base::precision">precision</A>
&#183; <A HREF="#ios_base::pword">pword</A>
&#183; <A HREF="#ios_base::register_callback">register_callback</A>
&#183; <A HREF="#ios_base::seekdir">seekdir</A>
&#183; <A HREF="#ios_base::setf">setf</A>
&#183; <A HREF="#ios_base::streamoff">streamoff</A>
&#183; <A HREF="#ios_base::streampos">streampos</A>
&#183; <A HREF="#ios_base::sync_with_stdio">sync_with_stdio</A>
&#183; <A HREF="#ios_base::unsetf">unsetf</A>
&#183; <A HREF="#ios_base::width">width</A>
&#183; <A HREF="#ios_base::xalloc">xalloc</A>
</CODE></B></P>
<HR>

<PRE>class <B>ios_base</B> {
public:
    class <B><A HREF="#ios_base::failure">failure</A></B>;
    typedef T1 <B><A HREF="#ios_base::fmtflags">fmtflags</A></B>;
    static const fmtflags <B>boolalpha</B>, <B>dec</B>, <B>fixed</B>, <B>hex</B>,
        <B>internal</B>, <B>left</B>, <B>oct</B>, <B>right</B>, <B>scientific</B>,
        <B>showbase</B>, <B>showpoint</B>, <B>showpos</B>, <B>skipws</B>, <B>unitbuf</B>,
        <B>uppercase</B>, <B>adjustfield</B>, <B>basefield</B>, <B>floatfield</B>;
    typedef T2 <B><A HREF="#ios_base::iostate">iostate</A></B>;
    static const iostate <B>badbit</B>, <B>eofbit</B>, <B>failbit</B>,
        <B>goodbit</B>;
    typedef T3 <B><A HREF="#ios_base::openmode">openmode</A></B>;
    static const openmode <B>app</B>, <B>ate</B>, <B>binary</B>, <B>in</B>, <B>out</B>,
        <B>trunc</B>;
    typedef T4 <B><A HREF="#ios_base::seekdir">seekdir</A></B>;
    typedef ::streamoff <B><A HREF="#ios_base::streamoff">streamoff</A></B>;
    typedef ::streampos <B><A HREF="#ios_base::streampos">streampos</A></B>;
    static const seekdir <B>beg</B>, <B>cur</B>, <B>end</B>;
    enum <B><A HREF="#ios_base::event">event</A></B> {
        <B>copyfmt_event</B>, <B>erase_event</B>,
        <B>imbue_event</B>};
    static const event <B>copyfmt_event</B>, <B>erase_event</B>,
        <B>copyfmt_event</B>;
    class <B><A HREF="#ios_base::Init">Init</A></B>;
    ios_base&amp; <B><A HREF="#ios_base::operator=">operator=</A></B>(const ios_base&amp; right);
    fmtflags <B><A HREF="#ios_base::flags">flags</A></B>() const;
    fmtflags <B><A HREF="#ios_base::flags">flags</A></B>(fmtflags newfmtflags);
    fmtflags <B><A HREF="#ios_base::setf">setf</A></B>(fmtflags newfmtflags);
    fmtflags <B><A HREF="#ios_base::setf">setf</A></B>(fmtflags newfmtflags, fmtflags mask);
    void <B><A HREF="#ios_base::unsetf">unsetf</A></B>(fmtflags mask);
    streamsize <B><A HREF="#ios_base::precision">precision</A></B>() const;
    streamsize <B><A HREF="#ios_base::precision">precision</A></B>(streamsize newprecision);