curs_getcchar.3x man page
getcchar, setcchar — Get a wide character string and rendition from a cchar_t or set a cchar_t from a wide-character string
const cchar_t *wcval,
void *opts );
const wchar_t *wch,
const attr_t attrs,
void *opts );
The getcchar function gets a wide-character string and rendition from a cchar_t argument. When wch is not a null pointer, the getcchar function does the following:
- Extracts information from a cchar_t value wcval
- Stores the character attributes in the location pointed to by attrs
- Stores the color-pair in the location pointed to by color_pair
- Stores the wide-character string, characters referenced by wcval, into the array pointed to by wch.
When wch is a null pointer, the getcchar function does the following:
- Obtains the number of wide characters pointed to by wcval
- Does not change the data referenced by attrs or color_pair
The setcchar function initializes the location pointed to by wcval by using:
- The character attributes in attrs
- The color pair in color_pair
The wide-character string pointed to by wch. The string must be L'\0' terminated, contain at most one spacing character, which must be the first.
Up to CCHARW_MAX-1 nonspacing characters may follow. Additional nonspacing characters are ignored.
The string may contain a single control character instead. In that case, no nonspacing characters are allowed.
X/Open Curses documents the opts argument as reserved for future use, saying that it must be null. This implementation uses that parameter in ABI 6 for the functions which have a color-pair parameter to support extended color pairs:
- For functions which modify the color, e.g., setcchar, if opts is set it is treated as a pointer to int, and used to set the color pair instead of the short pair parameter.
- For functions which retrieve the color, e.g., getcchar, if opts is set it is treated as a pointer to int, and used to retrieve the color pair as an int value, in addition retrieving it via the standard pointer to short parameter.
The wcval argument may be a value generated by a call to setcchar or by a function that has a cchar_t output argument. If wcval is constructed by any other means, the effect is unspecified.
When wch is a null pointer, getcchar returns the number of wide characters referenced by wcval, including one for a trailing null.
When wch is not a null pointer, getcchar returns OK upon successful completion, and ERR otherwise.
Upon successful completion, setcchar returns OK. Otherwise, it returns ERR.
Functions: curs_attr(3X), curs_color(3X), curses(3X), wcwidth(3).