X-Git-Url: https://ncurses.scripts.mit.edu/?p=ncurses.git;a=blobdiff_plain;f=doc%2Fhtml%2Fman%2Fcurs_inch.3x.html;h=d10727a5a1751327abc4cd7f0fd3a9b84eff16da;hp=ab5035e720d3468deb7fd14bdf08ecd722a1875b;hb=HEAD;hpb=17c5992a16be94247b83f2bbb9accdd9b7e7bb72 diff --git a/doc/html/man/curs_inch.3x.html b/doc/html/man/curs_inch.3x.html index ab5035e7..e2a00a62 100644 --- a/doc/html/man/curs_inch.3x.html +++ b/doc/html/man/curs_inch.3x.html @@ -1,7 +1,8 @@ - -curs_inch 3x - - +curs_inch 3x 2024-05-11 ncurses 6.5 Library calls + + -

curs_inch 3x

curs_inch 3x 2024-05-11 ncurses 6.5 Library calls

-curs_inch(3x)                                                    curs_inch(3x)
+curs_inch(3x)                    Library calls                   curs_inch(3x)

NAME

-       inch,  winch,  mvinch,  mvwinch - get a character and attributes from a
-       curses window
+       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);
+       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 posi-
-       tion, 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
+       winch  returns the curses character, including rendering 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

-       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.
+       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.
+       These functions do not return an error if the window comprises cells of
+       curses  complex characters (that is, 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
+       character data in the cell.

NOTES

-       Note that all of these routines may be macros.
+       inch, mvinch, and mvwinch may be implemented as macros.

PORTABILITY

-       These functions are described in the XSI Curses standard, Issue 4.
-
-       Very  old systems (before standardization) provide a different function
-       with the same name:
+       X/Open Curses, Issue 4 describes  these  functions.   It  specifies  no
+       error conditions for them.
 
-       o   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.
+

HISTORY

+       winch  was  implemented  in  the original 4BSD curses library (November
+       1980).  It returned only the character code (as an  integer)  with  the
+       "standout"  attribute bit (the only one it supported) cleared.  Because
+       7-bit ASCII was the only character  encoding  supported,  4BSD's  winch
+       returned a char type.
 
-       o   System  V  curses  added support for several video attributes which
-           could be combined with characters in the window.
+       System V  curses  (1983)  permitted  several rendering attributes to be
+       combined with a character in a window.   Reflecting  this  improvement,
+       winch  returned  an int in SVr3.2 (1988) and switched to chtype in SVr4
+       (1989).
 
-           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 equiva-
-       lents to these functions.
+       X/Open Curses does not specify the sizes of the character code or color
+       pair  identifier,  nor  the  quantity  of  rendering attribute bits, in
+       chtype; these are implementation-dependent.  ncurses  uses  eight  bits
+       for  the  character  code.   An application requiring a wider character
+       type, for instance to handle Unicode,  should  use  the  wide-character
+       counterparts of these functions.