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<PRE>void *&amp; <B>pword</B>(int idx);</PRE>

<P>The member function returns a reference to element <CODE>idx</CODE> of the
<A HREF="#extensible arrays">extensible array</A> with elements of type
<I>void</I> pointer. All elements are effectively present and initially
store the null pointer. The returned reference is invalid after the next
call to <CODE>pword</CODE> for the object,
after the object is altered by a call to
<CODE>ios::<A HREF="#ios::copyfmt">copyfmt</A></CODE>, or
after the object is destroyed.</P>

<P>If <CODE>idx</CODE> is negative, or if unique storage is unavailable
for the element, the function calls
<CODE><A HREF="#ios::setstate">setstate</A>(badbit)</CODE>
and returns a reference that might not be unique.</P>

<P>To obtain a unique index, for use across all objects of type
<CODE>ios_base</CODE>, call
<CODE><A HREF="#ios_base::xalloc">xalloc</A></CODE>.</P>

<H3><A NAME="ios_base::register_callback">
<CODE>ios_base::register_callback</CODE></A></H3>

<PRE>void <B>register_callback</B>(event_callback pfn, int idx);</PRE>

<P>The member function pushes the pair <CODE>{pfn, idx}</CODE>
onto the stored
<A HREF="#callback stack">callback stack</A>. When a
<A HREF="#callback event">callback event</A> <CODE>ev</CODE> is reported,
the functions are called, in reverse order of registry, by the
expression <CODE>(*pfn)(ev, *this, idx)</CODE>.</P>

<H3><A NAME="ios_base::seekdir"><CODE>ios_base::seekdir</CODE></A></H3>

<PRE>typedef T4 <B>seekdir</B>;
static const seekdir <B>beg</B>, <B>cur</B>, <B>end</B>;</PRE>

<P>The type is an enumerated type <CODE>T4</CODE> that describes an
object that can store the
<B><A NAME="seek mode">seek mode</A></B> used as an argument to the
member functions of several iostreams classes. The distinct flag values
are:</P>

<UL>
<LI><CODE><A NAME="ios_base::beg">beg</A></CODE>, to seek (alter the
current read or write position) relative to the beginning oc a sequence
(array, stream, or file)</LI>

<LI><CODE><A NAME="ios_base::cur">cur</A></CODE>, to seek relative to the
current position within a sequence</LI>

<LI><CODE><A NAME="ios_base::end">end</A></CODE>, to seek relative to the
end of a sequence</LI>
</UL>

<H3><A NAME="ios_base::setf"><CODE>ios_base::setf</CODE></A></H3>

<PRE>void <B>setf</B>(fmtflags newfmtflags);
fmtflags <B>setf</B>(fmtflags newfmtflags, fmtflags mask);</PRE>

<P>The first member function effectively calls
<CODE><A HREF="#ios_base::flags">flags</A>(newfmtflags | flags())</CODE> (set
selected bits), then returns the previous
<A HREF="#format flags">format flags</A>. The second member function
effectively calls
<CODE>flags(mask &amp; newfmtflags, flags() & ~mask)</CODE> (replace selected
bits under a mask), then returns the previous format flags.</P>

<H3><A NAME="ios_base::streamoff"><CODE>ios_base::streamoff</CODE></A></H3>

<PRE>typedef ::streamoff <B><A HREF="#ios_base::streamoff">streamoff</A></B>;</PRE>

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

<H3><A NAME="ios_base::streampos"><CODE>ios_base::streampos</CODE></A></H3>

<PRE>typedef ::streampos <B><A HREF="#ios_base::streampos">streampos</A></B>;</PRE>

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

<H3><A NAME="ios_base::sync_with_stdio"><CODE>ios_base::sync_with_stdio</CODE></A></H3>

<PRE>static bool <B>sync_with_stdio</B>(bool newsync = true);</PRE>

<P>The static member function stores a
<B><A NAME="stdio sync flag">stdio sync flag</A></B>, which is initially true.
When true, this flag ensures that operations on the same file are properly synchronized
between the <A HREF="lib_cpp.html#iostreams">iostreams</A> functions and those defined
in the <A HREF="index.html#Standard C Library">Standard C library</A>.
Otherwise, synchronization may or may not be guaranteed, but performance may be
improved.
The function stores <CODE>newsync</CODE> in the stdio sync flag and returns its
previous stored value. You can call it reliably only before performing any operations
on the <A HREF="lib_over.html#standard streams">standard streams</A>.</P>

<H3><A NAME="ios_base::unsetf"><CODE>ios_base::unsetf</CODE></A></H3>

<PRE>void <B>unsetf</B>(fmtflags mask);</PRE>

<P>The member function effectively calls
<CODE><A HREF="#ios_base::flags">flags</A>(~mask &amp; flags())</CODE>
(clear selected bits).</P>

<H3><A NAME="ios_base::width"><CODE>ios_base::width</CODE></A></H3>

<PRE>streamsize <B>width</B>() const;
streamsize <B>width</B>(streamsize newwidth);</PRE>

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

<H3><A NAME="ios_base::xalloc"><CODE>ios_base::xalloc</CODE></A></H3>

<PRE>static int <B>xalloc</B>();</PRE>

<P>The static member function returns a stored static value, which it
increments on each call. You can use the return value as a unique index
argument when calling the member functions
<CODE><A HREF="#ios_base::iword">iword</A></CODE> or
<CODE><A HREF="#ios_base::pword">pword</A></CODE>.</P>

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

<PRE>ios_base&amp; <B>left</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::left">left</A>, ios_base::
<A HREF="#ios_base::adjustfield">adjustfield</A>)</CODE>, then returns
<CODE>iosbase</CODE>.</P>

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

<PRE>class <B>locale</B> {
    };</PRE>

<P>The class serves as a placeholder for the much more elaborate locale
machinery mandated by Standard C++.</P>

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

<PRE>typedef T3 <B>mbstate_t</B>;</PRE>

<P>The type is an unspecified type <CODE>T3</CODE> that serves as a placeholder
for the more elaborate conversion-state machinery, used to convert between
multibyte and wide-character encodings, mandated by Standard C.</P>

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

<PRE>ios_base&amp; <B>oct</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::oct">oct</A>, ios_base::
<A HREF="#ios_base::basefield">basefield</A>)</CODE>, then returns
<CODE>iosbase</CODE>.</P>

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

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

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

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

<PRE>ios_base&amp; <B>scientific</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::scientific">scientific</A>, ios_base::
<A HREF="#ios_base::floatfield">floatfield</A>)</CODE>, then returns
<CODE>iosbase</CODE>.</P>

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

<PRE>ios_base&amp; <B>showbase</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::showbase">showbase</A>)</CODE>,
then returns <CODE>iosbase</CODE>.</P>

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

<PRE>ios_base&amp; <B>showpoint</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::showpoint">showpoint</A>)</CODE>, then returns
<CODE>iosbase</CODE>.</P>

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

<PRE>ios_base&amp; <B>showpos</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::showpos">showpos</A>)</CODE>,
then returns <CODE>iosbase</CODE>.</P>

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

<PRE>ios_base&amp; <B>skipws</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::skipws">skipws</A>)</CODE>,
then returns <CODE>iosbase</CODE>.</P>

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

<PRE>typedef T1 <B>streamoff</B>;</PRE>

<P>The type is a signed integer type <CODE>T1</CODE> that describes an
object that can store a byte offset involved in various stream
positioning operations. Its representation has at least 32 value bits.
It is <I>not</I> necessarily large enough to represent an arbitrary
byte position within a stream. The value <CODE>streamoff(-1)</CODE>
generally indicates an erroneous offset.</P>

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

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

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

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

<PRE>typedef T2 <B>streamsize</B>;</PRE>

<P>The type is a signed integer type <CODE>T3</CODE> that describes an
object that can store a count of the number of elements involved in
various stream operations. Its representation has at least 16 bits. It
is <I>not</I> necessarily large enough to represent an arbitrary byte
position within a stream.</P>

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

<PRE>ios_base&amp; <B>unitbuf</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::unitbuf">unitbuf</A>)</CODE>,
then returns <CODE>iosbase</CODE>.</P>

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

<PRE>ios_base&amp; <B>uppercase</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::uppercase">uppercase</A>)</CODE>, then returns
<CODE>iosbase</CODE>.</P>


<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_pjp.html">Copyright</A> &#169; 1992-2002
by P.J. Plauger. All rights reserved.</I></P>

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