curs_inch.3x - Linux manual page

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | NOTES | PORTABILITY | SEE ALSO | COLOPHON

curs_inch(3X)                                                  curs_inch(3X)

NAME         top

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

SYNOPSIS         top

       #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         top

       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.

       A_CHARTEXT     Bit-mask to extract character
       A_ATTRIBUTES   Bit-mask to extract attributes
       A_COLOR        Bit-mask to extract color-pair field information

RETURN VALUE         top

       Functions with a "mv" prefix first perform a cursor movement using
       wmove, and return an error if the position is outside the window, or
       if the window pointer is null.

       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         top

       Note that all of these routines may be macros.

PORTABILITY         top

       These functions are described in the XSI Curses standard, 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         top

       curses(3X)
            gives an overview of the WINDOW and chtype data types.

       curs_attr(3X)
            goes into more detail, pointing out portability problems and
            constraints on the use of chtype for returning window
            information.

       curs_in_wch(3X)
            describes comparable functions for the wide-character (ncursesw)
            library.

COLOPHON         top

       This page is part of the ncurses (new curses) project.  Information
       about the project can be found at 
       ⟨https://www.gnu.org/software/ncurses/ncurses.html⟩.  If you have a
       bug report for this manual page, send it to
       bug-ncurses-request@gnu.org.  This page was obtained from the
       project's upstream Git mirror of the CVS repository
       ⟨git://ncurses.scripts.mit.edu/ncurses.git⟩ on 2018-02-02.  (At that
       time, the date of the most recent commit that was found in the repos‐
       itory was 2018-01-30.)  If you discover any rendering problems in
       this HTML version of the page, or you believe there is a better or
       more up-to-date source for the page, or you have corrections or
       improvements to the information in this COLOPHON (which is not part
       of the original manual page), send a mail to man-pages@man7.org

                                                               curs_inch(3X)