asskoala/CKG
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
Files
0eb2d7c07d439a3a48ac0468c38afcc76bf1afc1
CKG/extern/stdcxx/4.2.1/doc/stdlibref/cout.html
Jose Caban 0eb2d7c07d first commit
2025-06-07 11:34:38 -04:00

299 lines
15 KiB
HTML
Raw Blame History

<!--
Licensed to the Apache Software Foundation (ASF) under one or more
contributor license agreements. See the NOTICE file distributed
with this work for additional information regarding copyright
ownership. The ASF licenses this file to you under the Apache
License, Version 2.0 (the License); you may not use this file
except in compliance with the License. You may obtain a copy of
the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
implied. See the License for the specific language governing
permissions and limitations under the License.
Copyright 1999-2007 Rogue Wave Software, Inc.
-->
<HTML>
<HEAD>
<TITLE>cout</TITLE>
<LINK REL=StyleSheet HREF="../rw.css" TYPE="text/css" TITLE="Apache stdcxx Stylesheet"></HEAD>
<BODY BGCOLOR=#FFFFFF>
<A HREF="count.html"><IMG SRC="images/bprev.gif" WIDTH=20 HEIGHT=21 ALT="Previous file" BORDER=O></A><A HREF="noframes.html"><IMG SRC="images/btop.gif" WIDTH=56 HEIGHT=21 ALT="Top of Document" BORDER=O></A><A HREF="booktoc.html"><IMG SRC="images/btoc.gif" WIDTH=56 HEIGHT=21 ALT="Contents" BORDER=O></A><A HREF="tindex.html"><IMG SRC="images/bindex.gif" WIDTH=56 HEIGHT=21 ALT="Index page" BORDER=O></A><A HREF="ctype.html"><IMG SRC="images/bnext.gif" WIDTH=25 HEIGHT=21 ALT="Next file" BORDER=O></A><DIV CLASS="DOCUMENTNAME"><B>Apache C++ Standard Library Reference Guide</B></DIV>
<H2>cout</H2>
<P><B>Library:</B>&nbsp;&nbsp;<A HREF="2-11.html">Input/output</A></P><UL>
<LI><A HREF="#sec1">Local Index</A></LI>
<LI><A HREF="#sec2">Summary</A></LI>
<LI><A HREF="#sec3">Synopsis</A></LI>
<LI><A HREF="#sec4">Description</A></LI>
<LI><A HREF="#sec5">Formatting</A></LI>
<LI><A HREF="#sec6">Description</A></LI>
<LI><A HREF="#sec7">Default Values</A></LI>
<LI><A HREF="#sec8">Warnings</A></LI>
<LI><A HREF="#sec9">See Also</A></LI>
<LI><A HREF="#sec10">Standards Conformance</A></LI>
</UL>
<A NAME="sec1"><H3>Local Index</H3></A>
No Entries
<A NAME="sec2"><H3>Summary</H3></A>
<P>Predefined stream that controls output to a stream buffer associated with the object <SAMP>stdout</SAMP> declared in <SAMP>&lt;cstdio&gt;</SAMP></P>
<A NAME="sec3"><H3>Synopsis</H3></A>
<PRE>#include &lt;iostream&gt;
namespace std {
extern ostream cout;
}
</PRE>
<A NAME="sec4"><H3>Description</H3></A>
<P>The object <SAMP>cout</SAMP> controls output to a stream buffer associated with the object <SAMP>stdout</SAMP> declared in <SAMP>&lt;cstdio&gt;</SAMP>. By default the standard C and C++ streams are synchronized, but performance improvement can be achieved by using the <B><I><A HREF="ios-base.html">ios_base</A></I></B> member function <SAMP>synch_with_stdio</SAMP> to desynchronize them.</P>
<P>After the object <SAMP>cin</SAMP> is initialized, <SAMP>cin.tie()</SAMP> returns <SAMP>&amp;cout</SAMP>, which implies that <SAMP>cin</SAMP> and <SAMP>cout</SAMP> are synchronized.</P>
<A NAME="sec5"><H3>Formatting</H3></A>
<P>The formatting is done through member functions or manipulators. </P>
<H4><A NAME="Table&nbsp;16">Table&nbsp;16: Formatting functions and manipulators for cout</A></H4>
<TABLE BORDER="1" CELLPADDING="3" CELLSPACING="3">
<tr><td valign=top><B>Manipulators</B>
</td>
<td valign=top><B>Member functions</B>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>showpos</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>setf(ios_base::showpos) </SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>noshowpos</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>unsetf(ios_base::showpos) </SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>showbase</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>setf(ios_base::showbase)</SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>noshowbase</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>unsetf(ios_base::showbase)</SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>uppercase</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>setf(ios_base::uppercase)</SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>nouppercase</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>unsetf(ios_base::uppercase)</SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>showpoint</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>setf(ios_base::showpoint)</SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>noshowpoint</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>unsetf(ios_base::showpoint)</SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>boolalpha</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>setf(ios_base::boolalpha)</SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>noboolalpha</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>unsetf(ios_base::boolalpha) </SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>unitbuf</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>setf(ios_base::unitbuf)</SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>nounitbuf</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>unsetf(ios_base::unitbuf)</SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>internal</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>setf(ios_base::internal,</SAMP></P>
<P CLASS="TABLE"><SAMP>ios_base::adjustfield)</SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>left</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>setf(ios_base::left,</SAMP></P>
<P CLASS="TABLE"><SAMP>ios_base::adjustfield)</SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>right</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>setf(ios_base::right,</SAMP></P>
<P CLASS="TABLE"><SAMP>ios_base::adjustfield)</SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>dec</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>setf(ios_base::dec,</SAMP></P>
<P CLASS="TABLE"><SAMP>ios_base::basefield)</SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>hex</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>setf(ios_base::hex,</SAMP></P>
<P CLASS="TABLE"><SAMP>ios_base::basefield) </SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>oct</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>setf(ios_base::oct,</SAMP></P>
<P CLASS="TABLE"><SAMP>ios_base::basefield)</SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>fixed</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>setf(ios_base::fixed,</SAMP></P>
<P CLASS="TABLE"><SAMP>ios_base::floatfield)</SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>scientific</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>setf(ios_base::scientific,</SAMP></P>
<P CLASS="TABLE"><SAMP>ios_base::floatfield)</SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>resetiosflags</SAMP></P>
<P CLASS="TABLE"><SAMP> (ios_base::fmtflags flag)</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>setf(0,flag)</SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>setiosflags</SAMP></P>
<P CLASS="TABLE"><SAMP>(ios_base::fmtflags flag)</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>setf(flag)</SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>setbase(int base)</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE">see above</P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>setfill(char_type c)</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>fill(c)</SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>setprecision(int n)</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>precision(n) </SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>setw(int n)</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>width(n)</SAMP></P>
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>endl</SAMP></P>
</td>
<td valign=top>&nbsp;
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>ends</SAMP></P>
</td>
<td valign=top>&nbsp;
</td>
</tr>
<tr><td valign=top><P CLASS="TABLE"><SAMP>flush</SAMP></P>
</td>
<td valign=top><P CLASS="TABLE"><SAMP>flush( )</SAMP></P>
</td>
</tr>
</TABLE>
<A NAME="sec6"><H3>Description</H3></A>
<P><TABLE CELLPADDING=3 BORDER=0>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>showpos</SAMP> </P></TD>
<TD CLASS="LIST"><P CLASS="LIST">Generates a + sign in non-negative generated numeric output.</P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>showbase</SAMP> </P></TD>
<TD CLASS="LIST"><P CLASS="LIST">Generates a prefix indicating the numeric base of generated integer output</P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>uppercase</SAMP> </P></TD>
<TD CLASS="LIST"><P CLASS="LIST">Replaces certain lowercase letters with their uppercase equivalents in generated output</P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>showpoint</SAMP> </P></TD>
<TD CLASS="LIST"><P CLASS="LIST">Generates a decimal-point character unconditionally in generated floating-point output</P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>boolalpha</SAMP> </P></TD>
<TD CLASS="LIST"><P CLASS="LIST">Inserts and extracts bool type in alphabetic format</P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>unitbuf</SAMP> </P></TD>
<TD CLASS="LIST"><P CLASS="LIST">Flushes output after each output operation</P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>internal</SAMP> </P></TD>
<TD CLASS="LIST"><P CLASS="LIST">Adds fill characters at a designated internal point in certain generated output. If no such point is designated, it's identical to <SAMP>right</SAMP>.</P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>left</SAMP> </P></TD>
<TD CLASS="LIST"><P CLASS="LIST">Adds fill characters on the right (final positions) of certain generated output</P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>right</SAMP> </P></TD>
<TD CLASS="LIST"><P CLASS="LIST">Adds fill characters on the left (initial positions) of certain generated output</P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>dec</SAMP> </P></TD>
<TD CLASS="LIST"><P CLASS="LIST">Converts integer input or generates integer output in decimal base</P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>hex</SAMP> </P></TD>
<TD CLASS="LIST"><P CLASS="LIST">Converts integer input or generates integer output in hexadecimal base</P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>oct</SAMP> </P></TD>
<TD CLASS="LIST"><P CLASS="LIST">Converts integer input or generates integer output in octal base</P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>fixed</SAMP> </P></TD>
<TD CLASS="LIST"><P CLASS="LIST">Generates floating-point output in fixed-point notation</P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>scientific</SAMP> </P></TD>
<TD CLASS="LIST"><P CLASS="LIST">Generates floating-point output in scientific notation</P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>resetiosflags(ios_base::fmtflags flag) </P></TD>
<TD CLASS="LIST"><P CLASS="LIST"></SAMP>Resets the <SAMP>fmtflags</SAMP> field <SAMP>flag</SAMP></P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>setiosflags(ios_base::fmtflags flag) </P></TD>
<TD CLASS="LIST"><P CLASS="LIST"></SAMP>Sets up the flag <SAMP>flag</SAMP></P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>setbase(int base)</SAMP> </P></TD>
<TD CLASS="LIST"><P CLASS="LIST">Converts integer input or generates integer output in base <SAMP>base</SAMP>. The parameter <SAMP>base</SAMP> can be 8, 10 or 16. </P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>setfill(char_type c) </P></TD>
<TD CLASS="LIST"><P CLASS="LIST"></SAMP>Sets the character used to pad (fill) an output conversion to the specified field width</P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>setprecision(int n)</SAMP> </P></TD>
<TD CLASS="LIST"><P CLASS="LIST">Sets the precision (number of digits after the decimal <SAMP>point) to generate on certain output conversions</SAMP></P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>setw(int n)</SAMP> </P></TD>
<TD CLASS="LIST"><P CLASS="LIST">Sets the field width (number of characters) to generate on certain output conversions</P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>endl</SAMP> </P></TD>
<TD CLASS="LIST"><P CLASS="LIST">Inserts a newline character into the output sequence and flushes the output buffer</P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>ends</SAMP> </P></TD>
<TD CLASS="LIST"><P CLASS="LIST">Inserts a null character into the output sequence</P></TD></TR>
<TR CLASS="LIST"><TD VALIGN="top" CLASS="LIST"><P CLASS="LIST"><SAMP>flush</SAMP> </P></TD>
<TD CLASS="LIST"><P CLASS="LIST">Flushes the output buffer</P></TD></TR>
</TABLE></P>
<A NAME="sec7"><H3>Default Values</H3></A>
<UL><PRE>precision() 6
width() 0
fill() the space character
flags() skipws | dec
getloc() locale::locale()
</PRE></UL>
<A NAME="sec8"><H3>Warnings</H3></A>
<P>Keep in mind that while the manipulator <SAMP>endl</SAMP> flushes the stream buffer, outputting the character <SAMP>'\n'</SAMP> is <I>not</I> guaranteed to flush the stream buffer. You should output the <SAMP>'\n'</SAMP> character without <SAMP>endl</SAMP> only if you do not need the buffer flushed. Note that outputting the <SAMP>'\n'</SAMP> character in such cases, and hence not forcing a buffer flush, may result in a performance improvement. It greatly improves performance when C and C++ streams are not synchronized.</P>
<A NAME="sec9"><H3>See Also</H3></A>
<P><B><I><A HREF="basic-ostream.html">basic_ostream</A></I></B>, <B><I><A HREF="basic-iostream.html">basic_iostream</A></I></B>, <B><I><A HREF="basic-filebuf.html">basic_filebuf</A></I></B>, <B><I><A HREF="cin.html">cin</A></I></B>, <B><I><A HREF="cerr.html">cerr</A></I></B>, <B><I><A HREF="clog.html">clog</A></I></B>, <B><I><A HREF="wcin.html">wcin</A></I></B>, <B><I><A HREF="wcout.html">wcout</A></I></B>, <B><I><A HREF="wcerr.html">wcerr</A></I></B>, <B><I><A HREF="wclog.html">wclog</A></I></B></P>
<A NAME="sec10"><H3>Standards Conformance</H3></A>
<P><I>ISO/IEC 14882:1998 -- International Standard for Information Systems --Programming Language C++, Section 27.3.1</I></P>
<BR>
<HR>
<A HREF="count.html"><IMG SRC="images/bprev.gif" WIDTH=20 HEIGHT=21 ALT="Previous file" BORDER=O></A><A HREF="noframes.html"><IMG SRC="images/btop.gif" WIDTH=56 HEIGHT=21 ALT="Top of Document" BORDER=O></A><A HREF="booktoc.html"><IMG SRC="images/btoc.gif" WIDTH=56 HEIGHT=21 ALT="Contents" BORDER=O></A><A HREF="tindex.html"><IMG SRC="images/bindex.gif" WIDTH=56 HEIGHT=21 ALT="Index page" BORDER=O></A><A HREF="ctype.html"><IMG SRC="images/bnext.gif" WIDTH=20 HEIGHT=21 ALT="Next file" BORDER=O></A>
<!-- Google Analytics tracking code -->
<script src="http://www.google-analytics.com/urchin.js" type="text/javascript">
</script>
<script type="text/javascript">
_uacct = "UA-1775151-1";
urchinTracker();
</script>
<!-- end of Google Analytics tracking code -->
</BODY>
</HTML>
Reference in New Issue View Git Blame Copy Permalink