.TH "md_src_plugins_ccode_README" 3elektra "Sun May 29 2016" "Version 0.8.14" "Elektra" \" -*- nroff -*-
.ad l
.nh
.SH NAME
md_src_plugins_ccode_README \- README 

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infos = Information about ccode plugin is in keys below
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infos/author = Markus Raab elektra@libelektra.org
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infos/licence = BSD
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infos/needs =
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infos/provides = code
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infos/placements = postgetstorage presetstorage
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infos/description = Decoding/Encoding engine which escapes unwanted characters\&.
.PP
.PP
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\&.
.PP
.SS "Restrictions"
.PP
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\&.
.PP
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\&.
.PP
.SS "C"
.PP
In the language C, following escape characters are present\&.
.PP
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\fCb\fP: backspace, hex: 08
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\fCt\fP: horizontal tab, hex: 09
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\fCn\fP: new line feed, hex: 0A
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\fCv\fP: vertical tab, hex: 0B
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\fCf\fP: form feed, hex: 0C
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\fCr\fP: carriage return, hex: 0D
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\fC\\\\\fP: back slash, hex: 5C
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\fC'\fP: single quote, hex: 27
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\fC"\fP: double quote, hex: 22
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\fC0\fP: null, hex: 00
.PP
.PP
This is also the default mapping\&.
.PP
.SS "Contract"
.PP
Add \fCccode\fP to \fCinfos/needs\fP for any plugin that you want to be filtered by ccode\&.