Topic summary
ISO-IR
Extracted from the Wikipedia article ISO/IEC 2022.
Registration of graphical and control code sets
ISO-IR registered escape sequences are also used encapsulated in a Formal Public Identifier to identify character sets used for numeric character references in SGML (ISO 8879). For example, the string ISO 646-1983//CHARSET International Reference Version (IRV)//ESC 2/5 4/0 can be used to identify the International Reference Version of ISO 646-1983, and the HTML 4.01 specification uses ISO Registration Number 177//CHARSET ISO/IEC 10646-1:1993 UCS-4 with implementation level 3//ESC 2/5 2/15 4/6 to identify Unicode. The textual representation of the escape sequence, included in the third element of the FPI, will be recognised by SGML implementations for supported character sets.