curs_get_wstr 3x

curs_get_wstr(3x)                                            curs_get_wstr(3x)




NAME

       get_wstr, getn_wstr, wget_wstr, wgetn_wstr, mvget_wstr, mvgetn_wstr,
       mvwget_wstr, mvwgetn_wstr - get an array of wide characters from a
       curses terminal keyboard


SYNOPSIS

       #include <curses.h>

       int get_wstr(wint_t *wstr);
       int getn_wstr(wint_t *wstr, int n);
       int wget_wstr(WINDOW *win, wint_t *wstr);
       int wgetn_wstr(WINDOW *win, wint_t *wstr, int n);
       int mvget_wstr(int y, int x, wint_t *wstr);
       int mvgetn_wstr(int y, int x, wint_t *wstr, int n);
       int mvwget_wstr(WINDOW *win, int y, int x, wint_t *wstr);
       int mvwgetn_wstr(WINDOW *win, int y, int x, wint_t *wstr, int n);


DESCRIPTION

       The  effect  of  get_wstr is as though a series of calls to get_wch(3x)
       were made, until a newline, other end-of-line, or end-of-file condition
       is  processed.  An end-of-file condition is represented by WEOF, as de-
       fined in <wchar.h>.  The newline and end-of-line conditions are  repre-
       sented  by  the  \n  wchar_t  value.   In all instances, the end of the
       string is terminated by a null wchar_t.  The routine  places  resulting
       values in the area pointed to by wstr.

       The  user's  erase and kill characters are interpreted.  If keypad mode
       is on for the window, KEY_LEFT and KEY_BACKSPACE  are  both  considered
       equivalent to the user's kill character.

       Characters  input  are  echoed  only  if echo is currently on.  In that
       case, backspace is echoed as deletion of the previous character  (typi-
       cally a left motion).

       The effect of wget_wstr is as though a series of calls to wget_wch were
       made.

       The effect of mvget_wstr is as though a call to move and then a  series
       of calls to get_wch were made.

       The  effect  of mvwget_wstr is as though a call to wmove and then a se-
       ries of calls to wget_wch were made.

       The getn_wstr, mvgetn_wstr, mvwgetn_wstr, and wgetn_wstr functions  are
       identical to the get_wstr, mvget_wstr, mvwget_wstr, and wget_wstr func-
       tions, respectively, except that the *n_* versions read at most n char-
       acters, letting the application prevent overflow of the input buffer.


NOTES

       Using  get_wstr,  mvget_wstr,  mvwget_wstr, or wget_wstr to read a line
       that overflows the array pointed to by wstr causes  undefined  results.
       The use of getn_wstr, mvgetn_wstr, mvwgetn_wstr, or wgetn_wstr, respec-
       tively, is recommended.

       These functions cannot return KEY_ values because there is  no  way  to
       distinguish a KEY_ value from a valid wchar_t value.

       All of these routines except wgetn_wstr may be macros.


RETURN VALUE

       All  of  these  functions return OK upon successful completion.  Other-
       wise, they return ERR.

       Functions using a window parameter return an error if it is null.

              wgetn_wstr
                   returns an error if the associated call to wget_wch failed.

       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.


PORTABILITY

       These functions are described in The Single Unix Specification, Version
       2.   No  error conditions are defined.  This implementation returns ERR
       if the window pointer is null, or if the lower-level wget_wch call  re-
       turns  an ERR.  In the latter case, an ERR return without other data is
       treated as an end-of-file condition, and the returned array contains  a
       WEOF followed by a null wchar_t.

       X/Open curses documented these functions to pass an array of wchar_t in
       1997, but that was an error because of this part of the description:

              The effect of get_wstr() is as  though  a  series  of  calls  to
              get_wch()  were  made,  until  a  newline character, end-of-line
              character, or end-of-file character is processed.

       The latter function  get_wch()  can  return  a  negative  value,  while
       wchar_t  is  a  unsigned type.  All of the vendors implement this using
       wint_t, following the standard.

       X/Open Curses, Issue 7 (2009) is unclear regarding whether  the  termi-
       nating null wchar_t value is counted in the length parameter n.  X/Open
       Curses, Issue 7 revised the corresponding description  of  wgetnstr  to
       address this issue.  The unrevised description of wget_nwstr can be in-
       terpreted either way.  This implementation counts the terminator in the
       length.

       X/Open  Curses  does  not specify what happens if the length n is nega-
       tive.

       o   For analogy with wgetnstr, ncurses  6.2  uses  a  limit  (based  on
           LINE_MAX).

       o   Some  other  implementations (such as Solaris xcurses) do the same,
           while others (PDCurses) do not allow this.

       o   NetBSD 7 curses imitates ncurses 6.1 in this regard, treating a  -1
           as an indefinite number of characters.


SEE ALSO

       Functions: curses(3x), curs_get_wch(3x), curs_getstr(3x).



                                                             curs_get_wstr(3x)