
\begin{DoxyItemize}
\item infos = Information about null plugin is in keys below
\item infos/author = Markus Raab \href{mailto:elektra@libelektra.org}{\texttt{ elektra@libelektra.\+org}}
\item infos/licence = B\+SD
\item infos/provides = code
\item infos/needs =
\item infos/placements = postgetstorage presetstorage
\item infos/status = maintained nodep libc nodoc
\item infos/metadata = binary
\item infos/description = Transforms null and empty values to text and back
\end{DoxyItemize}\hypertarget{md_src_plugins_null_README_src_plugins_null_README_md}{}\doxysection{Introduction}\label{md_src_plugins_null_README_src_plugins_null_README_md}
This plugin is a filter plugin which allows Elektra to better deal with null values and empty strings.

Elektra supports null values for binary keys. They differ from an empty string substantially in how they are handled. Some plugins that work on values are not aware of null values. They would crash when they try to access a value that is believed to be a string.\hypertarget{md_src_plugins_null_README_autotoc_md514}{}\doxysection{Special Values}\label{md_src_plugins_null_README_autotoc_md514}
The plugin transcodes all null values to {\ttfamily @N\+U\+LL}, all empty strings to {\ttfamily @E\+M\+P\+TY}, and all strings starting with {\ttfamily @} to begin with {\ttfamily @@}.\hypertarget{md_src_plugins_null_README_autotoc_md515}{}\doxysection{Usage}\label{md_src_plugins_null_README_autotoc_md515}
In order to use the {\ttfamily null} plugin you must add {\ttfamily null} to {\ttfamily infos/needs} in the plugin you wish to use.

Once {\ttfamily null} is included in {\ttfamily infos/needs}, the null plugin will filter values for the storage plugin. As a result, the storage plugin will never come across a null value or an empty string, instead it will be get strings with {\ttfamily @N\+U\+LL} and {\ttfamily @E\+M\+P\+TY} respectively. 