manpagez: man pages & more
man curs_get_wstr(3)
Home | html | info | man
curs_get_wstr(3)                                              curs_get_wstr(3)




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 defined
       in <wchar.h>.  The newline and end-of-line conditions are represented 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 (typically 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 series
       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
       functions, respectively, except that the *n_* versions read at most n
       characters, 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, 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.

       All of these routines except wgetn_wstr may be macros.


RETURN VALUE

       All of these functions return OK upon successful completion.  Otherwise,
       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 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

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



                                                               curs_get_wstr(3)

ncurses 6.4 - Generated Wed Jan 4 18:49:27 CST 2023
© manpagez.com 2000-2024
Individual documents may contain additional copyright information.