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curs_inch(3X)			 Library calls			 curs_inch(3X)

NAME
       inch, winch, mvinch, mvwinch - get a curses character from a window

SYNOPSIS
       #include	<curses.h>

       chtype inch(void);
       chtype winch(WINDOW * win);
       chtype mvinch(int y, int	x);
       chtype mvwinch(WINDOW * win, int	y, int x);

DESCRIPTION
       winch  returns the curses character, including its attributes and color
       pair identifier,	at the cursor position in the window win.   Subsection
       "Video  Attributes"  of	attron(3X)  explains how to extract these data
       from a chtype.  ncurses(3X) describes the variants of this function.

RETURN VALUE
       These functions return OK on success and	ERR on failure.

       In ncurses, they	return ERR if win is NULL.

       Functions prefixed with "mv" first perform cursor movement and fail  if
       the position (y,	x) is outside the window boundaries.

NOTES
       inch, mvinch, and mvwinch may be	implemented as macros.

       These functions do not fail if the window contains cells	of curses com-
       plex  characters;  that is, if they contain characters with codes wider
       than eight bits (or greater than	255 as an unsigned  decimal  integer).
       They  instead  extract  only  the low-order eight bits of the character
       code from the cell.

PORTABILITY
       X/Open Curses Issue 4 describes these functions.	 It specifies no error
       conditions for them.

HISTORY
       The original curses in 4BSD (1980) defined winch	as a  macro  accessing
       the  WINDOW  structure member representing character cell data, at that
       time a char, containing only a 7-bit ASCII character code and a "stand-
       out" attribute bit, the only one	the library supported.

       SVr2 curses (1984) extended this	approach, widening the character  code
       to  eight bits and permitting several attributes	to be combined with it
       by storing them together	in a chtype, an	alias of unsigned short.   Be-
       cause  a	 macro	was used, its value was	not type-checked as a function
       return value could have been.  Goodheart	documented SVr3	 (1987)	 winch
       as  returning  an  int.	 SVr3.1's (1987) chtype	became an alias	of un-
       signed long, using 16 bits for the character code and widening the type
       in practical terms to 32	bits, as 64-bit	Unix systems were not  yet  in
       wide  use,  and	fixed-width integral types would not be	standard until
       ISO C99.	 SVr3.2	(1988) added a 6-bit color pair	 identifier  alongside
       the attributes.

SEE ALSO
       curs_in_wch(3X)	describes  comparable functions	of the ncurses library
       in its wide-character configuration (ncursesw).

       curses(3X), curs_instr(3X)

ncurses	6.6			  2025-02-15			 curs_inch(3X)

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