.TH "md_doc_help_elektra-introduction" 3elektra "Sun May 29 2016" "Version 0.8.14" "Elektra" \" -*- nroff -*-
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.SH NAME
md_doc_help_elektra-introduction \- elektra-introduction(7) -- an introduction to Elektra 
\fBElektra\fP is a library implementing access to a global key database\&. The Global key database provides global access to all key databases of all applications in a system that wants to access a key database\&. To elektrify an application means to change the application so that it uses Elektra afterwards\&.
.PP
Information on Elektra can be found on the \fCwebsite\fP\&. For introduction in the terminology, make sure to read \fBthe glossary\fP\&.
.SH "Motivation"
.PP
.SS "Why Elektra?"
.PP
Configurations, settings and preferences are hierarchical data structures of keys, each consisting of a name and a value\&. They can be used to configure software for the user's needs\&. Because these settings stay the same across restarts of the program, they need to be stored permanently\&. In the beginning this was done with primitive text files\&. Possibilities to structure the text were added later\&.
.PP
Nearly every system developed its own way to read preferences, but some systems can also change them\&. Because the graphical user interface can be tweaked in many ways, the most encompassing systems emerged from this area\&. Some got a de facto standard for a desktop environment (kconfig, gconfig) or even an operating system (Windows Registry, Open Directory)\&. But they have a common problem: they are bound to the platform for which they were developed\&. On the other hand, there are many libraries that do a good job in parsing and writing configuration files\&. These tools are, however, not powerful enough to keep the configuration independent from the operating system's details, for example, how to resolve the file name of the configuration file\&.
.PP
That is where Elektra comes in to fill the gap\&. On the one hand, Elektra is not tied to any platform or operating system\&. On the other hand, Elektra is powerful enough to be useful immediately for what it is written for: to access configuration\&.
.PP
.SS "Why is it important?"
.PP
The configuration files that represent key databases can have binary or humanly-readable formats\&. From the latter, an unmanageable number is established\&. Developers of programs tend to document the format of the configuration file extensively\&. The configuration file may give a special flavour to a specific program and users frequently need it\&.
.PP
Sometimes limitations in the configuration file even lead to rewrites of software\&. For example, inetd has a non-modular flat configuration file that is not extensible because of a limited number of rows\&. In order to extend its functionality, the program had to be rewritten with a new approach to configuration: xinetd emerged\&. Both of these projects are now almost defined by their configuration files giving them identity and separating them from each other\&. Elektra has introduced \fBbackend\fP to support the storage of key databases in different formats\&.
.PP
Elektra abstracts configuration so that applications can receive and store settings without carrying information about how and where these are actually stored\&. It is the purpose of the backends to implement these details\&. What makes the difference is the situation that every program can access any configuration because of the abstraction\&. In the example of inetd, Elektra allows an elektrified inetd respective xinetd to store its configuration in /etc/inetd\&.conf respective /etc/xinetd\&.conf\&. Additionally, each other program interested in these preferences can access them in a uniform way\&.
.PP
To support a global key database, a mutual agreement on some level is needed\&. Elektra provides this common layer with its data structures\&. Each elektrified application lies on top of this abstraction layer and it can talk to each part of the global key database using the classes presented next\&.