curs_in_wch.3x man page
in_wch, mvin_wch, mvwin_wch, win_wch — extract a complex character and rendition from a window
int in_wch(cchar_t *wcval);
int mvin_wch(int y, int x, cchar_t *wcval);
int mvwin_wch(WINDOW *win, int y, int x, cchar_t *wcval);
int win_wch(WINDOW *win, cchar_t *wcval);
These functions extract the complex character and rendition from the current position in the named window into the cchar_t object referenced by wcval.
No errors are defined in the XSI Curses standard. This implementation checks for null pointers, returns ERR in that case. Also, the mv routines check for error moving the cursor, returning ERR in that case. Otherwise they return OK
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.
Note that all of these routines may be macros.
These functions are described in the XSI Curses standard, Issue 4.