bionic (3) md_src_plugins_ccode_README.3elektra.gz

NAME

       md_src_plugins_ccode_READMEREADME
        -

       • infos = Information about ccode plugin is in keys below

       • infos/author = Markus Raab elektra@libelektra.org

       • infos/licence = BSD

       • infos/needs =

       • infos/provides = code

       • infos/placements = postgetstorage presetstorage

       • infos/description = Decoding/Encoding engine which escapes unwanted characters.

       When writing a C string in C code some characters cannot be expressed directly but have a special one
       letter abbreviation. The ccode plugin allows us to map any single escaped character to be replaced by
       another single character and vice versa. The user can configure this mapping.

   Restrictions
       This method of encoding characters is not as powerful as the hexcode plugin in terms of reduction. The
       hexcode plugin allows reduction of the character set to '0'-'9', 'a'-'f' and one escape character. So it
       can represent any key value with only 17 characters. On the other hand, ccode cannot reduce the set more
       than by half.

       So when all control characters and non-ASCII characters need to vanish, it cannot be done with the ccode
       plugin. But it is perfectly suitable to reduce by some characters. The advantages are that the size only
       doubles in the worst case and that it is much easier to read.

   C
       In the language C, following escape characters are present.

       • b: backspace, hex: 08

       • t: horizontal tab, hex: 09

       • n: new line feed, hex: 0A

       • v: vertical tab, hex: 0B

       • f: form feed, hex: 0C

       • r: carriage return, hex: 0D

       • \\: back slash, hex: 5C

       • ': single quote, hex: 27

       • ": double quote, hex: 22

       • 0: null, hex: 00

       This is also the default mapping.

   Contract
       Add ccode to infos/needs for any plugin that you want to be filtered by ccode.