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curs_scanw(3X)							curs_scanw(3X)

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

       #include	<curses.h>

       int scanw(char *fmt, ...);
       int wscanw(WINDOW *win, char *fmt, ...);
       int mvscanw(int y, int x, char *fmt, ...);
       int mvwscanw(WINDOW *win, int y,	int x, char *fmt, ...);
       int vw_scanw(WINDOW *win, char *fmt, va_list varglist);
       int vwscanw(WINDOW *win,	char *fmt, va_list varglist);

       The scanw, wscanw and mvscanw routines  are  analogous  to  scanf  [see
       scanf(3)].   The	 effect	 of  these  routines is	as though wgetstr were
       called on the window, and the resulting line  used  as  input  for  ss-
       canf(3).	  Fields  which	 do not	map to a variable in the fmt field are

       The vwscanw and vw_scanw	routines are analogous to vscanf.   They  per-
       form  a wscanw using a variable argument	list.  The third argument is a
       va_list,	a pointer to a list of arguments, as defined in	<stdarg.h>.

       vwscanw returns ERR on failure and an integer equal to  the  number  of
       fields scanned on success.

       Applications  may  use the return value from the	scanw, wscanw, mvscanw
       and mvwscanw routines to	determine the  number  of  fields  which  were
       mapped in the call.

       The  XSI	Curses standard, Issue 4 describes these functions.  The func-
       tion vwscanw is marked TO BE WITHDRAWN, and is  to  be  replaced	 by  a
       function	 vw_scanw  using  the  <stdarg.h>  interface.  The Single Unix
       Specification, Version 2	states that vw_scanw  is preferred to  vwscanw
       since  the  latter requires including <varargs.h>, which	cannot be used
       in the same file	as <stdarg.h>.	This  implementation  uses  <stdarg.h>
       for both, because that header is	included in <curses.h>.

       Both  XSI and The Single	Unix Specification, Version 2 state that these
       functions return	ERR or OK.  Since the underlying scanf can return  the
       number  of  items scanned, and the SVr4 code was	documented to use this
       feature,	this is	probably an editing error which	was introduced in XSI,
       rather  than  being  done  intentionally.  Portable applications	should
       only test if the	return value is	ERR, since  the	 OK  value  (zero)  is
       likely  to be misleading.  One possible way to get useful results would
       be to use a "%n"	conversion at the end of the format string  to	ensure
       that something was processed.

       curses(3X), curs_getstr(3X), curs_printw(3X), scanf(3)



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