Provided by: ncurses-doc_6.5+20251123-1_all bug

NAME

       get_wstr,  getn_wstr,  wget_wstr, wgetn_wstr, mvget_wstr, mvgetn_wstr, mvwget_wstr, mvwgetn_wstr - read a
       wide-character string from a curses terminal keyboard

SYNOPSIS

       #include <curses.h>

       int get_wstr(wint_t * wstr);
       int wget_wstr(WINDOW * win, wint_t * wstr);
       int mvget_wstr(int y, int x, wint_t * wstr);
       int mvwget_wstr(WINDOW * win, int y, int x, wint_t * wstr);

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

DESCRIPTION

       wget_wstr  populates  a  user-supplied  wide-character  string  buffer   wstr   by   repeatedly   calling
       wget_wch(3NCURSES)  with  the  win argument until a line feed or carriage return character is input.  The
       function

       •   does not copy the terminating character to wstr;

       •   populates wstr with WEOF (as defined in wchar.h) if an end-of-file condition occurs on the input;

       •   always terminates the string with a null wide character (after any WEOF);

       •   interprets  the  screen's  wide  erase  and  wide  kill  characters  (see  erasewchar(3NCURSES)   and
           killwchar(3NCURSES));

       •   recognizes function keys only if the screen's keypad option is enabled (see keypad(3NCURSES));

       •   treats the function keys KEY_LEFT and KEY_BACKSPACE the same as the wide erase character; and

       •   discards  function  key  inputs  other  than those treated as the wide erase or wide kill characters,
           calling beep(3NCURSES).

       The wide erase character replaces the character at the end of the buffer  with  a  null  wide  character,
       while the wide kill character does the same for the entire buffer.

       If   the   screen's   echo   option   is   enabled  (see  echo(3NCURSES)),  wget_wstr  updates  win  with
       wadd_wch(3NCURSES).  Further,

       •   the wide erase character and its function key synonyms move the cursor to the left, and

       •   the wide kill character returns the cursor to where it was located when wget_wstr was called.

       wgetn_wstr is similar, but reads at most n wide characters, aiding the application to  avoid  overrunning
       the  buffer  to which wstr points.  curses ignores an attempt to input more than n wide characters (other
       than the terminating line feed or carriage return), calling beep(3NCURSES).  If n is negative, wgetn_wstr
       reads up to LINE_MAX wide characters (see sysconf(3)).

       ncurses(3NCURSES) describes the variants of these functions.

RETURN VALUE

       These functions return OK on success and ERR on failure.

       In ncurses, these functions fail if

       •   the curses screen has not been initialized,

       •   (for functions taking a WINDOW pointer argument) win is a null pointer,

       •   wstr is a null pointer, or

       •   an internal wget_wch(3NCURSES) call fails.

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

NOTES

       All of these functions except wgetn_wstr may be implemented as macros.

       Reading input that overruns the buffer pointed to by wstr causes undefined results.   Use  the  n-infixed
       functions, and allocate sufficient storage for wstr — at least n+1 times sizeof(wchar_t).

       These  functions cannot store a KEY_ value in wstr because there is no way to distinguish it from a valid
       wchar_t value.

       While these functions conceptually implement a series of calls to wget_wch, they also temporarily  change
       properties  of  the  curses screen to permit simple editing of the input buffer.  Each function saves the
       screen's  state,  calls  nl(3NCURSES),  and,  if  the  screen   was   in   canonical   (“cooked”)   mode,
       cbreak(3NCURSES).  Before returning, it restores the saved screen state.  Other implementations differ in
       detail,  affecting  which  control  characters  they  can accept in the buffer; see section “PORTABILITY”
       below.

       Unlike getstr(3NCURSES) and related functions of ncurses's non-wide API, these functions  do  not  return
       KEY_RESIZE if a SIGWINCH event interrupts the function.

EXTENSIONS

       getn_wstr,  wgetn_wstr,  mvgetn_wstr,  and  mvwgetn_wstr's  handing  of  negative  n values is an ncurses
       extension.

PORTABILITY

       Applications  employing  ncurses  extensions  should  condition  their  use  on  the  visibility  of  the
       NCURSES_VERSION preprocessor macro.

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

       Issue 4  documented  these  functions  as passing an array of wchar_t, but that was an error, conflicting
       with the following language in the standard.

              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.

       get_wch can return a negative value (WEOF), but wchar_t is a unsigned type.  All of the vendors implement
       these functions using wint_t, following the Issue 7 standard.

       X/Open  Curses  Issue 7  is  unclear whether the terminating null wide character counts toward the length
       parameter n.  A similar issue affected wgetnstr in Issue 4, Version 2; Issue 7  revised  that  function's
       description  to  address the issue, but not that of wget_nwstr, leaving it ambiguous.  ncurses counts the
       terminator in the length.

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

       •   For consistency with wgetnstr, ncurses 6.2 uses a limit based on LINE_MAX.

       •   Some other implementations (such as Solaris xcurses) do the same,  while  others  (PDCurses)  do  not
           permit a negative n.

       •   NetBSD 7 curses imitates ncurses 6.1 and earlier, treating a negative n as an unbounded count of wide
           characters.

       Implementations vary in their handling of input control characters.

       •   While  they  may  enable  the screen's echo option, some do not take it out of raw mode, and may take
           cbreak mode into account when deciding whether to handle echoing within wgetn_wstr or to rely  on  it
           as a side effect of calling wget_wch.

           Since  1995,  ncurses  has  provided  handlers  for  SIGINTR  and SIGQUIT events, which are typically
           generated at the keyboard with ^C and ^\ respectively.  In cbreak mode, those handlers catch a signal
           and stop the program, whereas other implementations write those characters into the buffer.

       •   Starting with ncurses 6.3 (2021), wgetn_wstr preserves raw mode if the screen  was  already  in  that
           state, allowing one to enter the characters the terminal interprets as interrupt and quit events into
           the buffer, for consistency with SVr4 curses's wgetnstr.

HISTORY

       X/Open  Curses  Issue 4  (1995)  initially  specified these functions.  The System V Interface Definition
       Version 4 of the same year specified functions named wgetwstr and wgetnwstr  (and  the  usual  variants).
       These  were  later  additions  to  SVr4.x, not appearing in the first SVr4 (1989).  Except in name, their
       declarations did not differ from X/Open's later wget_wstr and wgetn_wstr  until  X/Open  Curses  Issue  7
       (2009) eventually changed the type of the buffer argument to a pointer to wint_t.

SEE ALSO

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

       ncurses(3NCURSES), get_wch(3NCURSES)

ncurses 6.5                                        2025-10-20                                 get_wstr(3NCURSES)