An escape sequence is source-code notation beginning with a backslash. In C, the Unicode escape \u followed by four hexadecimal digits encodes a code point inside a multibyte string. section 14.3
Encoding ä
The code point for “latin small letter a with diaeresis” is U+00E4, so a string can contain "\u00E4". A capital U followed by eight hexadecimal digits provides the larger form, but specialized contexts rarely require it. section 14.3
#define VBAR "\u2502" /**< a vertical bar character */ #define HBAR "\u2500" /**< a horizontal bar character */ #define TOPLEFT "\u250c" /**< topleft corner character */ #define TOPRIGHT "\u2510" /**< topright corner character */
These C macro definitions use Unicode escape sequences to name box-drawing characters such as vertical bars, corners, and horizontal bars. section 14.3
Keep these distinctions in mind:
- Use \u followed by four hexadecimal digits for a code point within the 65,536-code-point range addressed by four digits. section 14.3
- Treat the escape as encoded character data, not as a guarantee that ordinary string functions will count or search multibyte characters correctly. section 14.3
