ostream.html

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conversion specification is <CODE>lo</CODE> and the converted value is
<CODE>(long)val</CODE>.</LI>

<LI>If <CODE>flags() &amp; ios_base::basefield ==
ios_base::<A HREF="ios.html#ios_base::hex">hex</A></CODE>, the
conversion specification is <CODE>lx</CODE> and the converted value is
<CODE>(unsigned long)val</CODE>.</LI>

<LI>Otherwise, the conversion specification is <CODE>ld</CODE>
and the converted value is <CODE>(long)val</CODE>.</LI>
</UL>

<P>If <CODE><A HREF="ios.html#ios_base::width">width</A>()</CODE>
is nonzero, a field width of this value is prepended. The
function then calls <CODE>width(0)</CODE> to reset the
field width to zero.</P>

<P>Finally:</P>

<UL>
<LI>If <CODE>flags() &amp;
ios_base::<A HREF="ios.html#ios_base::showpos">showpos</A></CODE>
is nonzero, the flag <CODE>+</CODE> is prepended to the conversion
specification.</LI>

<LI>If <CODE>flags() &amp;
ios_base::<A HREF="ios.html#ios_base::showbase">showbase</A></CODE>
is nonzero, the flag <CODE>#</CODE> is prepended to the conversion
specification.</LI>
</UL>

<P>The function returns <CODE>*this</CODE>.</P>

<P>The functions:</P>

<PRE>ostream&amp; <B>operator&lt;&lt;</B>(float val);
ostream&amp; <B>operator&lt;&lt;</B>(double val);
ostream&amp; <B>operator&lt;&lt;</B>(long double val);</PRE>

<P>each convert <CODE>val</CODE> to a
<B><A NAME="floating-point output field">floating-point output field</A></B>
and insert it.
A period (<CODE>.</CODE>) separates the integer digits from the
fraction digits.
The equivalent print conversion specification is determined as follows:</P>

<UL>
<LI>If <CODE><A HREF="ios.html#ios_base::flags">flags</A>() &amp;
ios_base::<A HREF="ios.html#ios_base::floatfield">floatfield</A> ==
ios_base::<A HREF="ios.html#ios_base::fixed">fixed</A></CODE>, the
conversion specification is <CODE>f</CODE>.</LI>

<LI>If <CODE>flags() &amp; ios_base::floatfield ==
ios_base::<A HREF="ios.html#ios_base::scientific">scientific</A></CODE>, the
conversion specification is <CODE>e</CODE>.
If <CODE>flags() &amp;
ios_base::<A HREF="ios.html#ios_base::uppercase">uppercase</A></CODE>
is nonzero, <CODE>e</CODE> is replaced with <CODE>E</CODE>.</LI>

<LI>Otherwise, the conversion specification is <CODE>g</CODE>.
If <CODE>flags() &amp; ios_base::uppercase</CODE>
is nonzero, <CODE>g</CODE> is replaced with <CODE>G</CODE>.</LI>
</UL>

<P>If <CODE>val</CODE> has type <I>double,</I> the function prepends <CODE>l</CODE>
to the conversion specification. If <CODE>val</CODE> has type <I>long double,</I>
it prepends <CODE>L</CODE> to the conversion specification.</P>

<P>If <CODE>flags() &amp; ios_base::fixed</CODE> is nonzero, or if
<CODE><A HREF="ios.html#ios_base::precision">precision</A>()</CODE>
is greater than zero, a precision with the value
<CODE>precision()</CODE> is prepended to the conversion specification.
Any <A HREF="#padding">padding</A> behaves the same
as for an integer output field.

<P>If <CODE><A HREF="ios.html#ios_base::width">width</A>()</CODE>
is nonzero, a field width of this value is prepended. The
function then calls <CODE>width(0)</CODE> to reset the
field width to zero. Finally:</P>

<UL>
<LI>If <CODE>flags() &amp;
ios_base::<A HREF="ios.html#ios_base::showpos">showpos</A></CODE>
is nonzero, the flag <CODE>+</CODE> is prepended to the conversion
specification.</LI>

<LI>If <CODE>flags() &amp;
ios_base::<A HREF="ios.html#ios_base::showpoint">showpoint</A></CODE>
is nonzero, the flag <CODE>#</CODE> is prepended to the conversion
specification.</LI>
</UL>

<H3><A NAME="ostream::put"><CODE>ostream::put</CODE></A></H3>

<PRE>ostream&amp; <B><A HREF="#ostream::put">put</A></B>(char_type ch);</PRE>

<P>The <A HREF="#unformatted output functions">unformatted output function</A>
inserts the element <CODE>ch</CODE>. It returns <CODE>*this</CODE>.</P>

<H3><A NAME="ostream::seekp"><CODE>ostream::seekp</CODE></A></H3>

<PRE>ostream&amp; <B>seekp</B>(pos_type pos);
ostream&amp; <B>seekp</B>(off_type off,
    ios_base::seek_dir way);</PRE>

<P>If <CODE><A HREF="ios.html#ios::fail">fail</A>()</CODE> is false,
the first member function calls
<CODE>newpos = <A HREF="ios.html#ios::rdbuf">rdbuf</A>()-&gt;
<A HREF="streambu.html#streambuf::pubseekpos">pubseekpos</A>(pos,
<A HREF="ios.html#ios_base::out">out</A>)</CODE>,
for some <CODE>pos_type</CODE> temporary object <CODE>newpos</CODE>.
If <CODE>fail()</CODE> is false, the second function calls
<CODE>newpos = rdbuf()-&gt;
<A HREF="streambu.html#streambuf::pubseekoff">pubseekoff</A>(off, way,
<A HREF="ios.html#ios_base::out">out</A>)</CODE>.
In either case, if <CODE>(off_type)newpos == (off_type)(-1)</CODE>
(the positioning operation fails) the function calls
<CODE>istr.<A HREF="ios.html#ios::setstate">setstate</A>(failbit)</CODE>.
Both functions return <CODE>*this</CODE>.</P>

<H3><A NAME="ostream::sentry"><CODE>ostream::sentry</CODE></A></H3>

<PRE>class <B>sentry</B> {
public:
    explicit <B>sentry</B>(ostream&amp; ostr);
    <B>operator bool</B>() const;
    <B>~sentry</B>();
private:
    <B>sentry</B>(const sentry&amp;);  // not defined
    sentry&amp; <B>operator=</B>(const sentry&amp;);  // not defined
    bool <B>status</B>;
    };</PRE>

<P>The nested class describes an object whose declaration structures the
<A HREF="#formatted output functions">formatted output functions</A>
and the
<A HREF="#unformatted output functions">unformatted output functions</A>.
If <CODE>ostr.<A HREF="ios.html#ios::good">good</A>()</CODE> is true, and
<CODE>ostr.<A HREF="ios.html#ios::tie">tie</A>()</CODE> is not
a null pointer, the constructor calls
<CODE>ostr.tie-&gt;<A HREF="#ostream::flush">flush</A>()</CODE>.
The constructor then stores the value returned by <CODE>ostr.good()</CODE>
in <B>status</B>.
A later call to <CODE>operator bool()</CODE> delivers this stored value.</P>

<P>If
<CODE><A HREF="ios.html#ios_base::flags">flags</A>() &amp;
<A HREF="ios.html#ios_base::unitbuf">unitbuf</A></CODE> is nonzero,
the destructor calls
<CODE><A HREF="#ostream::flush">flush</A>()</CODE>.</P>

<H3><A NAME="ostream::tellp"><CODE>ostream::tellp</CODE></A></H3>

<PRE>pos_type <B>tellp</B>();</PRE>

<P>If <CODE><A HREF="ios.html#ios::fail">fail</A>()</CODE> is false,
the member function returns
<CODE><A HREF="ios.html#ios::rdbuf">rdbuf</A>()-&gt;
<A HREF="streambu.html#streambuf::pubseekoff">pubseekoff</A>(0,
<A HREF="ios.html#ios_base::cur">cur</A>,
<A HREF="ios.html#ios_base::in">in</A>)</CODE>.
Otherwise, it returns <CODE>pos_type(-1)</CODE>.</P>

<H3><A NAME="ostream::write"><CODE>ostream::write</CODE></A></H3>

<PRE>ostream&amp; <B>write</B>(const char_type *str, streamsize count);</PRE>

<P>The <A HREF="#unformatted output functions">unformatted output function</A>
inserts the sequence of <CODE>count</CODE> elements
beginning at <CODE>str</CODE>.</P>

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

<PRE>ostream <B>endl</B>(ostream&amp; ostr);</PRE>

<P>The manipulator calls
<CODE>ostr.<A HREF="#ostream::put">put</A>(ostr.
<A HREF="ios.html#ios::widen">widen</A>('\n'))</CODE>,
then calls
<CODE>ostr.<A HREF="#ostream::flush">flush</A>()</CODE>.
It returns <CODE>ostr</CODE>.</P>

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

<PRE>ostream&amp; <B>ends</B>(ostream&amp; ostr);</PRE>

<P>The manipulator calls
<CODE>ostr.<A HREF="#ostream::put">put</A>(Elem('\0'))</CODE>.
It returns <CODE>ostr</CODE>.</P>

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

<PRE>ostream&amp; <B>flush</B>(ostream&amp; ostr);</PRE>

<P>The manipulator calls
<CODE>ostr.<A HREF="#ostream::flush">flush</A>()</CODE>.
It returns <CODE>ostr</CODE>.</P>

<H2><A NAME="operator&lt;&lt;"><CODE>operator&lt;&lt;</CODE></A></H2>

<PRE>ostream&amp;
    <B>operator&lt;&lt;</B>(ostream&amp; ostr, const char *str);
ostream&amp;
    <B>operator&lt;&lt;</B>(ostream&amp; ostr, char ch);
ostream&amp;
    <B>operator&lt;&lt;</B>(ostream&amp; ostr, const signed char *str);
ostream&amp;
    <B>operator&lt;&lt;</B>(ostream&amp; ostr, signed char ch);
ostream&amp;
    <B>operator&lt;&lt;</B>(ostream&amp; ostr, const unsigned char *str);
ostream&amp;
    <B>operator&lt;&lt;</B>(ostream&amp; ostr, unsigned char ch);</PRE>

<P>All of these functions are
<A HREF="#formatted output functions">formatted output functions</A>.
The function:</P>

<PRE>ostream&amp;
    <B>operator&lt;&lt;</B>(ostream&amp; ostr, const char *str);</PRE>

<P>determines the length <CODE>N =
traits_type::<A HREF="string2.html#char_traits::length">length</A>(str)</CODE>
of the sequence beginning at <CODE>str</CODE>, and inserts the sequence. If
<CODE>N &lt; ostr.<A HREF="ios.html#ios_base::width">width</A>()</CODE>,
then the function also inserts a repetition of <CODE>ostr.width() - N</CODE>
<A HREF="ios.html#fill character">fill characters</A>.
The repetition precedes the sequence if
<CODE>(ostr.<A HREF="ios.html#ios_base::flags">flags</A>() &amp;
<A HREF="ios.html#ios_base::adjustfield">adjustfield</A> !=
<A HREF="ios.html#ios_base::left">left</A></CODE>.
Otherwise, the repetition follows the sequence.
The function returns <CODE>ostr</CODE>.</P>

<P>The function:</P>

<PRE>ostream&amp;
    <B>operator&lt;&lt;</B>(ostream&amp; ostr, char ch);</PRE>

<P>inserts the element <CODE>ch</CODE>. If
<CODE>1 &lt; ostr.<A HREF="ios.html#ios_base::width">width</A>()</CODE>,
then the function also inserts a repetition of <CODE>ostr.width() - 1</CODE>
<A HREF="ios.html#fill character">fill characters</A>.
The repetition precedes the sequence if
<CODE>(ostr.<A HREF="ios.html#ios_base::flags">flags</A>() &amp;
<A HREF="ios.html#ios_base::adjustfield">adjustfield</A> !=
<A HREF="ios.html#ios_base::left">left</A></CODE>.
Otherwise, the repetition follows the sequence.
It returns <CODE>ostr</CODE>.</P>

<P>The function:</P>

<PRE>ostream&amp;
    <B>operator&lt;&lt;</B>(ostream&amp; ostr, const signed char *str);</PRE>

<P>returns <CODE>ostr &lt;&lt; (const char *)str</CODE>.</P>

<P>The function:</P>

<PRE>ostream&amp;
    <B>operator&lt;&lt;</B>(ostream&amp; ostr, signed char ch);</PRE>

<P>returns <CODE>ostr &lt;&lt; (char)ch</CODE>.</P>

<P>The function:</P>

<PRE>ostream&amp;
    <B>operator&lt;&lt;</B>(ostream&amp; ostr, const unsigned char *str);</PRE>

<P>returns <CODE>ostr &lt;&lt; (const char *)str</CODE>.</P>

<P>The function:</P>

<PRE>ostream&amp;
    <B>operator&lt;&lt;</B>(ostream&amp; ostr, unsigned char ch);</PRE>

<P>returns <CODE>ostr &lt;&lt; (char)ch</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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