# curs_get_wstr 3x 2024-04-20 ncurses 6.5 Library calls

    curs_get_wstr(3x)                Library calls               curs_get_wstr(3x)

## NAME

           get_wstr,  getn_wstr,  wget_wstr,  wgetn_wstr, mvget_wstr, mvgetn_wstr,
           mvwget_wstr, mvwgetn_wstr - get a wide-character string 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  function  wgetn_wstr  is  equivalent  to  a  series  of  calls  to
           wget_wch(3x) until a newline or carriage return terminates the series:

           o   The terminating character is not included in the returned string.

           o   An end-of-file condition is represented  by  WEOF,  as  defined  in
               <wchar.h>.

           o   In  all  instances,  the  end of the string is terminated by a null
               wchar_t.

           o   The function stores the result in the area pointed to by  the  wstr
               parameter.

           o   The function reads at most n characters, thus preventing a possible
               overflow of the input buffer.

               Any attempt to enter more characters (other  than  the  terminating
               newline or carriage return) causes a beep.

               Function keys also cause a beep and are ignored.

           The user's erase and kill characters are interpreted:

           o   The  erase  character (e.g., ^H) erases the character at the end of
               the buffer, moving the cursor to the left.

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

           o   The kill character (e.g., ^U) erases the entire buffer, leaving the
               cursor at the beginning of the buffer.

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

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

## RETURN VALUE

           All  of  these  functions  return  the  integer  OK   upon   successful
           completion.  If unsuccessful, they return ERR.

           X/Open defines no error conditions.

           In this implementation, these functions return an error

           o   if the window pointer is null,

           o   if its timeout expires without having any data, or

           o   if the associated call to wget_wch failed.

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

## NOTES

           Any of these functions other than wgetn_wstr may be macros.

           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,
           respectively, is recommended.

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

## 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 returns 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
           terminating 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 interpreted either way.  This implementation counts
           the terminator in the length.

           X/Open Curses does  not  specify  what  happens  if  the  length  n  is
           negative.

           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

           curs_getstr(3x) describes comparable functions of the  ncurses  library
           in its non-wide-character configuration.

           curses(3x), curs_get_wch(3x)

    ncurses 6.5                       2024-04-20                 curs_get_wstr(3x)