1curs_get_wch(3X)                                              curs_get_wch(3X)
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NAME

6       get_wch,  wget_wch,  mvget_wch,  mvwget_wch,  unget_wch  - get (or push
7       back) a wide character from curses terminal keyboard
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SYNOPSIS

10       #include <curses.h>
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12       int get_wch(wint_t *wch);
13       int wget_wch(WINDOW *win, wint_t *wch);
14       int mvget_wch(int y, int x, wint_t *wch);
15       int mvwget_wch(WINDOW *win, int y, int x, wint_t *wch);
16       int unget_wch(const wchar_t wch);
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DESCRIPTION

19       The get_wch, wget_wch, mvget_wch, and mvwget_wch functions read a char‐
20       acter  from  the terminal associated with the current or specified win‐
21       dow.  In no-delay mode, if no  input  is  waiting,  the  value  ERR  is
22       returned.   In  delay  mode,  the program waits until the system passes
23       text through to the program.  Depending on the setting of cbreak,  this
24       is  after  one  character  (cbreak  mode),  or  after the first newline
25       (nocbreak mode).  In half-delay mode, the program waits until the  user
26       types a character or the specified timeout interval has elapsed.
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28       Unless  noecho has been set, these routines echo the character into the
29       designated window.
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31       If the window is not a pad and has been moved  or  modified  since  the
32       last call to wrefresh, wrefresh will be called before another character
33       is read.
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35       If keypad is enabled, these functions respond  to  the  pressing  of  a
36       function key by setting the object pointed to by wch to the correspond‐
37       ing KEY_ value defined in <curses.h> and returning KEY_CODE_YES.  If  a
38       character  (such  as  escape) that could be the beginning of a function
39       key is received, curses sets a timer.  If the remainder of the sequence
40       does arrive within the designated time, curses passes through the char‐
41       acter; otherwise, curses returns the function key value.  For this rea‐
42       son,  many terminals experience a delay between the time a user presses
43       the escape key and the time the escape is returned to the program.
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45       The unget_wch function pushes the wide character wch back onto the head
46       of  the input queue, so the wide character is returned by the next call
47       to get_wch.  The pushback of one character is guaranteed.  If the  pro‐
48       gram  calls  unget_wch  too  many  times without an intervening call to
49       get_wch, the operation may fail.
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NOTES

52       The header file  <curses.h>  automatically  includes  the  header  file
53       <stdio.h>.
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55       Applications  should  not  define the escape key by itself as a single-
56       character function.
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58       When using get_wch, wget_wch, mvget_wch,  or  mvwget_wch,  applications
59       should not use nocbreak mode and echo mode at the same time.  Depending
60       on the state of the tty driver when each character is typed,  the  pro‐
61       gram may produce undesirable results.
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63       All functions except wget_wch and unget_wch may be macros.
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RETURN VALUE

66       When  get_wch,  wget_wch,  mvget_wch, and mvwget_wch functions success‐
67       fully report the pressing of a function key, they return  KEY_CODE_YES.
68       When they successfully report a wide character, they return OK.  Other‐
69       wise, they return ERR.
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71       Upon successful completion, unget_wch returns OK.  Otherwise, the func‐
72       tion returns ERR.
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74       Functions  with  a  "mv"  prefix  first perform a cursor movement using
75       wmove, and return an error if the position is outside the window, or if
76       the window pointer is null.
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SEE ALSO

79       curses(3X),    curs_getch(3X),    curs_ins_wch(3X),    curs_inopts(3X),
80       curs_move(3X), curs_refresh(3X)
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84                                                              curs_get_wch(3X)
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