display the language name of an lstlisting under the rule

Question

I am writing code form different languages in one document. Because of that it would be nice, if it is possible to display the name of the language below the rule of an lstlisting.

This is my code

\documentclass{article}

\usepackage{listings}
\usepackage{xcolor}

\lstset{
%   backgroundcolor=\color{},
    commentstyle=\color{green},
    keywordstyle=\color{blue},
    stringstyle=\color{black!50!green},
    %        identifierstyle=\color{red},
    numbers=left,
    captionpos=t,
    showstringspaces=false,
    tabsize=2,
    frame=b,
    breaklines=true,
    xleftmargin=17pt,
    framexleftmargin=17pt,
}

\begin{document}


    Much text
    \begin{lstlisting}[language=C++]
#inlcude <iostream.h>

int end = 5;

for(int i = 0; i < end; i++)
{
    std::cout << "Hello world!";
}
    \end{lstlisting}

%This should happen automaticly
%----------------------------------------------------

 \begin{flushright}
    c++
 \end{flushright}

%----------------------------------------------------

\end{document}

Answer 1

With the package etoolbox you can hook to the lstlisting environment to store the language option in a macro. Then you can add code after the environment to display the flushright environment with the language.

MWE:

\documentclass{article}

\usepackage{listings}
\usepackage{xcolor}
\usepackage{etoolbox}

\makeatletter
\AtEndEnvironment{lstlisting}{\xdef\xlang{\lst@language}}
\AfterEndEnvironment{lstlisting}{\begin{flushright}\xlang\end{flushright}}
\makeatother

\lstset{
%   backgroundcolor=\color{},
    commentstyle=\color{green},
    keywordstyle=\color{blue},
    stringstyle=\color{black!50!green},
    %        identifierstyle=\color{red},
    numbers=left,
    captionpos=t,
    showstringspaces=false,
    tabsize=2,
    frame=b,
    breaklines=true,
    xleftmargin=17pt,
    framexleftmargin=17pt,
}

\begin{document}


    Much text
    \begin{lstlisting}[language=C++]
#include <iostream.h>

int end = 5;

for(int i = 0; i < end; i++)
{
    std::cout << "Hello world!";
}
    \end{lstlisting}

\begin{lstlisting}[language=bash]
echo "Hello world!"
\end{lstlisting}

\end{document}

Result: