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The recode reference manual

2.1 Overview of charsets

Recoding is currently possible between many charsets, the bulk of which is described by RFC 1345 tables or available in the iconv library. See section 7. Tabular sources (RFC 1345), and see section 6. The iconv library. The recode library also handles some charsets in some specialised ways. These are:

• 6-bit charsets based on CDC display code: 6/12 code from NOS; bang-bang code from Université de Montréal;

• 7-bit ASCII: without any diacritics, or else: using backspace for overstriking; Unisys' Icon convention; TeX/LaTeX coding; easy French conventions for electronic mail;

• 8-bit extensions to ASCII: ISO Latin-1, Atari ST code, IBM's code for the PC, Apple's code for the Macintosh;

• 8-bit non-ASCII codes: three flavours of EBCDIC;

• 16-bit or 31-bit universal characters, and their transfer encodings.

The introduction of RFC 1345 in recode has brought with it a few charsets having the functionality of older ones, but yet being different in subtle ways. The effects have not been fully investigated yet, so for now, clashes are avoided, the old and new charsets are kept well separate.

Conversion is possible between almost any pair of charsets. Here is a list of the exceptions. One may not recode from the flat, count-characters or dump-with-names charsets, nor from or to the data, tree or :libiconv: charsets. Also, if we except the data and tree pseudo-charsets, charsets and surfaces live in disjoint recoding spaces, one cannot really transform a surface into a charset or vice-versa, as surfaces are only meant to be applied over charsets, or removed from them.