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
These routines return the character, of type chtype, at the current position in the named window. If any attributes are set for that position, their values are OR'ed into the value returned. Constants defined in <curses.h> can be used with the & (logical AND) operator to extract the character or attributes alone.
Attributes
The following bit masks may be AND-ed with characters returned by winch.
Name | Description |
A_CHARTEXT | Extract character |
A_ATTRIBUTES | Extract attributes |
A_COLOR | Extract color pair information |
RETURN VALUE
Functions prefixed with “mv” first perform cursor movement and fail if the position (y, x) is outside the window boundaries.
The winch function does not return an error if the window contains characters larger than 8-bits (255). Only the low-order 8 bits of the character are used by winch.
NOTES
Note that all of these routines may be macros.
PORTABILITY
These functions are described in X/Open Curses, Issue 4.
Very old systems (before standardization) provide a different function with the same name:
- •
- The winch function was part of the original BSD curses library, which stored a 7-bit character combined with the standout attribute.
- In BSD curses, winch returned only the character (as an integer) with the standout attribute removed.
- •
- System V curses added support for several video attributes which could be combined with characters in the window.
- Reflecting this improvement, the function was altered to return the character combined with all video attributes in a chtype value.
X/Open Curses does not specify the size and layout of attributes, color and character values in chtype; it is implementation-dependent. This implementation uses 8 bits for character values. An application using more bits, e.g., a Unicode value, should use the wide-character equivalents to these functions.
SEE ALSO
curs_in_wch(3X) describes comparable functions of the ncurses library in its wide-character configuration (ncursesw).
2024-04-20 | ncurses 6.5 |