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curs_insch 3x 2025-03-08 ncurses 6.5 Library calls

curs_insch(3x)                   Library calls                  curs_insch(3x)

NAME

       insch,  winsch,  mvinsch,  mvwinsch  -  insert  a curses character in a
       window

SYNOPSIS

       #include <curses.h>

       int insch(chtype ch);
       int winsch(WINDOW * win, chtype ch);
       int mvinsch(int y, int x, chtype ch);
       int mvwinsch(WINDOW * win, int y, int x, chtype ch);

DESCRIPTION

       winsch inserts the curses character ch at the cursor  position  in  the
       window  win.   The  character  previously  at the cursor and any to its
       right move one cell to the right; the formerly rightmost  character  on
       the  line  is discarded.  Unlike addch(3x), winsch does not advance the
       cursor.  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

       o   the curses screen has not been initialized, or

       o   (for functions taking a WINDOW pointer  argument)  win  is  a  null
           pointer.

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

NOTES

       insch, mvinsch, and mvwinsch may be implemented as macros.

       curses does not  necessarily  employ  the  terminal's  insert_character
       (ich1) capability to achieve insertion.

PORTABILITY

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

       SVr4 describes a successful return value  only  as  "an  integer  value
       other than ERR".

HISTORY

       SVr2 (1984) introduced these functions.