1curs_scanw(3X)                                                  curs_scanw(3X)
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NAME

6       scanw, wscanw, mvscanw, mvwscanw, vwscanw, vw_scanw - convert formatted
7       input from a curses window
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SYNOPSIS

10       #include <curses.h>
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12       int scanw(char *fmt, ...);
13       int wscanw(WINDOW *win, char *fmt, ...);
14       int mvscanw(int y, int x, char *fmt, ...);
15       int mvwscanw(WINDOW *win, int y, int x, char *fmt, ...);
16       int vw_scanw(WINDOW *win, char *fmt, va_list varglist);
17       int vwscanw(WINDOW *win, char *fmt, va_list varglist);
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DESCRIPTION

20       The scanw, wscanw and mvscanw routines  are  analogous  to  scanf  [see
21       scanf(3)].   The  effect  of  these  routines is as though wgetstr were
22       called on the  window,  and  the  resulting  line  used  as  input  for
23       sscanf(3).   Fields which do not map to a variable in the fmt field are
24       lost.
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26       The vwscanw and vw_scanw routines are  analogous  to  vscanf(3).   They
27       perform a wscanw using a variable argument list.  The third argument is
28       a va_list, a pointer to a list of arguments, as defined in <stdarg.h>.
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RETURN VALUE

31       vwscanw returns ERR on failure and an integer equal to  the  number  of
32       fields scanned on success.
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34       Applications  may  use the return value from the scanw, wscanw, mvscanw
35       and mvwscanw routines to determine the  number  of  fields  which  were
36       mapped in the call.
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38       Functions  with  a  "mv"  prefix  first perform a cursor movement using
39       wmove, and return an error if the position is outside the window, or if
40       the window pointer is null.
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PORTABILITY

43       The  XSI Curses standard, Issue 4 describes these functions.  The func‐
44       tion vwscanw is marked TO BE WITHDRAWN, and is  to  be  replaced  by  a
45       function  vw_scanw  using  the  <stdarg.h>  interface.  The Single Unix
46       Specification, Version 2 states that vw_scanw  is preferred to  vwscanw
47       since  the  latter requires including <varargs.h>, which cannot be used
48       in the same file as <stdarg.h>.  This  implementation  uses  <stdarg.h>
49       for both, because that header is included in <curses.h>.
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51       Both  XSI and The Single Unix Specification, Version 2 state that these
52       functions return ERR or OK.  Since the underlying scanf(3)  can  return
53       the  number  of  items scanned, and the SVr4 code was documented to use
54       this feature, this is probably an editing error which was introduced in
55       XSI,  rather  than  being  done  intentionally.   Portable applications
56       should only test if the return value is ERR, since the OK value  (zero)
57       is  likely  to  be  misleading.  One possible way to get useful results
58       would be to use a "%n" conversion at the end of the  format  string  to
59       ensure that something was processed.
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SEE ALSO

62       curses(3X), curs_getstr(3X), curs_printw(3X), scanf(3)
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66                                                                curs_scanw(3X)
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