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== References ==
#REDIRECT [[C / C++]]
See also [[C|C references]].

<ul>
<li>[http://www.cplusplus.com/reference/ www.cplusplus.com &mdash; C++ Reference]</li>
* Including [http://www.cplusplus.com/reference/clibrary/ C Language Library]
* and ... [http://www.cplusplus.com/reference/iostream/ IOStream Library]
<li> [http://www.sgi.com/tech/stl/ SGI &mdash; Standard Template Library Programmer's Guide]</li>
<li> [http://www.research.att.com/~bs/hopl-almost-final.pdf Evolving a language in and for the real world: C++ 1991-2006, Bjarne Stroustrup] (pdf)</li>
<li> manpage <tt>stl-manual</tt> (from SGI)</li>
<source lang="bash">
sudo apt-get install stl-manual
ln -s /usr/share/doc/stl-manual/html /var/www/sgi # Now the manual is available at http://localhost/sgi
</source>
</ul>

=== References - local copy ===
<source lang="bash">
# Make a local copy of www.cplusplus.com - use option -P http://proxy:port if needed
httrack http://www.cplusplus.com/ -W -O /var/www -%v "-www.cplusplus.com/forum/*" "-www.cplusplus.com/src/*" "-www.cplusplus.com/member/*"
</source>

== Benchmark ==
=== Between compilers ===
* '''g++'''
* '''[http://www.phoronix.com/scan.php?page=article&item=pathscale_ekopath4_open&num=1 EKOPath4]''', a recently open-sourced compiler with much better performance than gcc/g++.
* '''Intel compiler'''
* '''pathCC''', PathScale compiler

=== Between languages ===
* C++ reported to be the ''fastest language'', even faster than C and java. See [http://shootout.alioth.debian.org/ The Computer Language Benchmarks Game]
*[http://developers.slashdot.org/story/11/06/15/0242237/C-the-Clear-Winner-In-Googles-Language-Performance-Tests C++ the Clear Winner In Google's Language Performance Tests]

== Nested Classes ==
See [http://publib.boulder.ibm.com/infocenter/comphelp/v8v101/index.jsp?topic=%2Fcom.ibm.xlcpp8a.doc%2Flanguage%2Fref%2Fcplr061.htm Nested classes on ibm.com].

== Tips ==

{| class=wikitable width="100%"
!Problem
!width="600px"|Solution
|-
|Overloading operators <code>i++</code> or <code>++i</code><br/>See [http://www.parashift.com/c++-faq-lite/operator-overloading.html#faq-13.14] for more details.
|

{{nb|<source lang="c">
class Number {
public:
// prefix ++ - Must return (*this)
Number& operator++ ();
// postfix ++ - Must never return (*this) by reference
Number operator++ (int); // ... OR ....
void operator++ (int);
};
</source>}}
|-
|Reset <code>ostringstream</code>
|
{{nb|<source lang="c">
ostringstream oss;
oss << "Hello," << 123 << endl;
string s = oss.str();

oss.str(""); // oss empty now - we can reuse it
oss << "World!" << 456 << endl;
</source>}}
|}

== Security Tips ==

{| class=wikitable width="100%"
!Problem
!width="600px"|Solution
|-
| Use <code>mlock()</code> to prevent a section of memory from swapping to disk<br/>(source: "Building Secure Software," John Viega & Gary McGraw)
|
|}

== Tools ==
=== GNU cflow ===
'''GNU cflow''' analyzes a collection of C source files and prints a graph, charting control flow within the program.

GNU cflow is able to produce both direct and inverted flowgraphs for C sources. Optionally a cross-reference listing can be
generated. Two output formats are implemented: POSIX and GNU (extended).

== &lt;iostream.h&gt; or &lt;iostream&gt; ==
* <code>&lt;iostream&gt;</code> is the standard compliant library. <code>&lt;iostream.h&gt;</code> is deprecated since many many years.
* <code>&lt;iostream&gt;</code> contains a set of templatized I/O classes which support both ''narrow'' and ''wide'' characters (by contrast, <code>&lt;iostream.h&gt;</code> classes are confined to ''char'' exclusively).
* Third, the C++ standard specification of iostream's interface was changed in many subtle aspects. Consequently, the interfaces and implementation of <code>&lt;iostream&gt;</code> differ from <code>&lt;iostream.h&gt;</code>.
* Finally, <code>&lt;iostream&gt;</code> components are declared in namespace <u><code>std</code></u> whereas <code>&lt;iostream.h&gt;</code> components are declared in the global scope.
Note that both libraries '''cannot''' be mixed in one program.

Revision as of 09:07, 22 June 2011

References

See also C references.

References - local copy

# Make a local copy of www.cplusplus.com - use option -P http://proxy:port if needed
httrack http://www.cplusplus.com/ -W -O /var/www -%v "-www.cplusplus.com/forum/*" "-www.cplusplus.com/src/*" "-www.cplusplus.com/member/*"

Benchmark

Between compilers

  • g++
  • EKOPath4, a recently open-sourced compiler with much better performance than gcc/g++.
  • Intel compiler
  • pathCC, PathScale compiler

Between languages

Nested Classes

See Nested classes on ibm.com.

Tips

Problem Solution
Overloading operators i++ or ++i
See [1] for more details.
class Number {
public:
    // prefix ++ - Must return (*this)
    Number& operator++ ();    
    // postfix ++ - Must never return (*this) by reference
    Number  operator++ (int);  // ... OR ....
    void  operator++ (int);   
};
Reset ostringstream
ostringstream oss;
oss << "Hello," << 123 << endl;
string s = oss.str();

oss.str("");                  // oss empty now - we can reuse it
oss << "World!" << 456 << endl;

Security Tips

Problem Solution
Use mlock() to prevent a section of memory from swapping to disk
(source: "Building Secure Software," John Viega & Gary McGraw)

Tools

GNU cflow

GNU cflow analyzes a collection of C source files and prints a graph, charting control flow within the program.

GNU cflow is able to produce both direct and inverted flowgraphs for C sources. Optionally a cross-reference listing can be generated. Two output formats are implemented: POSIX and GNU (extended).

<iostream.h> or <iostream>

  • <iostream> is the standard compliant library. <iostream.h> is deprecated since many many years.
  • <iostream> contains a set of templatized I/O classes which support both narrow and wide characters (by contrast, <iostream.h> classes are confined to char exclusively).
  • Third, the C++ standard specification of iostream's interface was changed in many subtle aspects. Consequently, the interfaces and implementation of <iostream> differ from <iostream.h>.
  • Finally, <iostream> components are declared in namespace std whereas <iostream.h> components are declared in the global scope.

Note that both libraries cannot be mixed in one program.