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  42 <H1 class="no-header">curs_scanw 3x</H1>
  43 <PRE>
  44 <STRONG><A HREF="curs_scanw.3x.html">curs_scanw(3x)</A></STRONG>                                                  <STRONG><A HREF="curs_scanw.3x.html">curs_scanw(3x)</A></STRONG>
  45
  46
  47
  48
  49 </PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
  50        <STRONG>scanw</STRONG>, <STRONG>wscanw</STRONG>, <STRONG>mvscanw</STRONG>, <STRONG>mvwscanw</STRONG>, <STRONG>vwscanw</STRONG>, <STRONG>vw_scanw</STRONG> - convert formatted
  51        input from a <STRONG>curses</STRONG> window
  52
  53
  54 </PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
  55        <STRONG>#include</STRONG> <STRONG>&lt;curses.h&gt;</STRONG>
  56
  57        <STRONG>int</STRONG> <STRONG>scanw(const</STRONG> <STRONG>char</STRONG> <STRONG>*fmt,</STRONG> <STRONG>...);</STRONG>
  58        <STRONG>int</STRONG> <STRONG>wscanw(WINDOW</STRONG> <STRONG>*win,</STRONG> <STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*fmt,</STRONG> <STRONG>...);</STRONG>
  59        <STRONG>int</STRONG> <STRONG>mvscanw(int</STRONG> <STRONG>y,</STRONG> <STRONG>int</STRONG> <STRONG>x,</STRONG> <STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*fmt,</STRONG> <STRONG>...);</STRONG>
  60        <STRONG>int</STRONG> <STRONG>mvwscanw(WINDOW</STRONG> <STRONG>*win,</STRONG> <STRONG>int</STRONG> <STRONG>y,</STRONG> <STRONG>int</STRONG> <STRONG>x,</STRONG> <STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*fmt,</STRONG> <STRONG>...);</STRONG>
  61        <STRONG>int</STRONG> <STRONG>vw_scanw(WINDOW</STRONG> <STRONG>*win,</STRONG> <STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*fmt,</STRONG> <STRONG>va_list</STRONG> <STRONG>varglist);</STRONG>
  62
  63        /* obsolete */
  64        <STRONG>int</STRONG> <STRONG>vwscanw(WINDOW</STRONG> <STRONG>*win,</STRONG> <STRONG>const</STRONG> <STRONG>char</STRONG> <STRONG>*fmt,</STRONG> <STRONG>va_list</STRONG> <STRONG>varglist);</STRONG>
  65
  66
  67 </PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
  68        The <STRONG>scanw</STRONG>, <STRONG>wscanw</STRONG> and <STRONG>mvscanw</STRONG> routines  are  analogous  to  <STRONG>scanf</STRONG>  [see
  69        <STRONG>scanf(3)</STRONG>].   The  effect  of  these  routines is as though <STRONG>wgetstr</STRONG> were
  70        called on the  window,  and  the  resulting  line  used  as  input  for
  71        <STRONG>sscanf(3)</STRONG>.   Fields which do not map to a variable in the <EM>fmt</EM> field are
  72        lost.
  73
  74        The <STRONG>vwscanw</STRONG> and <STRONG>vw_scanw</STRONG> routines are  analogous  to  <STRONG>vscanf(3)</STRONG>.   They
  75        perform a <STRONG>wscanw</STRONG> using a variable argument list.  The third argument is
  76        a <EM>va</EM><STRONG>_</STRONG><EM>list</EM>, a pointer to a list of arguments, as defined in <STRONG>&lt;stdarg.h&gt;</STRONG>.
  77
  78
  79 </PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
  80        <STRONG>vwscanw</STRONG> returns <STRONG>ERR</STRONG> on failure and an integer equal to  the  number  of
  81        fields scanned on success.
  82
  83        Applications  may  use the return value from the <STRONG>scanw</STRONG>, <STRONG>wscanw</STRONG>, <STRONG>mvscanw</STRONG>
  84        and <STRONG>mvwscanw</STRONG> routines to determine the  number  of  fields  which  were
  85        mapped in the call.
  86
  87        Functions  with  a  "mv"  prefix  first perform a cursor movement using
  88        <STRONG>wmove</STRONG>, and return an error if the position is outside the window, or if
  89        the window pointer is null.
  90
  91
  92 </PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
  93        In this implementation, <STRONG>vw_scanw</STRONG> and <STRONG>vwscanw</STRONG> are equivalent, to support
  94        legacy applications.  However, the latter (<STRONG>vwscanw</STRONG>) is obsolete:
  95
  96        <STRONG>o</STRONG>   The XSI Curses standard, Issue 4 described these functions,  noting
  97            that  the  function <STRONG>vwscanw</STRONG> is marked TO BE WITHDRAWN, and is to be
  98            replaced by a function <STRONG>vw_scanw</STRONG> using the <STRONG>&lt;stdarg.h&gt;</STRONG> interface.
  99
 100        <STRONG>o</STRONG>   The Single Unix Specification, Version 2 states that  <STRONG>vw_scanw</STRONG>   is
 101            preferred   to   <STRONG>vwscanw</STRONG>   since   the  latter  requires  including
 102            <STRONG>&lt;varargs.h&gt;</STRONG>, which cannot be used in the same file  as  <STRONG>&lt;stdarg.h&gt;</STRONG>.
 103            This  implementation  uses <STRONG>&lt;stdarg.h&gt;</STRONG> for both, because that header
 104            is included in <STRONG>&lt;curses.h</STRONG>&gt;.
 105
 106        <STRONG>o</STRONG>   X/Open Curses, Issue 5 (December 2007) marked <STRONG>vwscanw</STRONG>  (along  with
 107            <STRONG>vwprintw</STRONG> and the termcap interface) as withdrawn.
 108
 109        Both  XSI and The Single Unix Specification, Version 2 state that these
 110        functions return <STRONG>ERR</STRONG> or <STRONG>OK</STRONG>.
 111
 112        <STRONG>o</STRONG>   Since the underlying  <STRONG>scanf(3)</STRONG>  can  return  the  number  of  items
 113            scanned, and the SVr4 code was documented to use this feature, this
 114            is probably an editing error which was introduced  in  XSI,  rather
 115            than being done intentionally.
 116
 117        <STRONG>o</STRONG>   This  implementation  returns the number of items scanned, for com-
 118            patibility with SVr4  curses.   As  of  2018,  NetBSD  curses  also
 119            returns  the  number  of  items  scanned.   Both ncurses and NetBSD
 120            curses call <STRONG>vsscanf</STRONG> to scan the string, which returns <STRONG>EOF</STRONG> on error.
 121
 122        <STRONG>o</STRONG>   Portable applications should only test if the return value is  <STRONG>ERR</STRONG>,
 123            since the <STRONG>OK</STRONG> value (zero) is likely to be misleading.
 124
 125            One  possible way to get useful results would be to use a "%n" con-
 126            version at the end of the format string to  ensure  that  something
 127            was processed.
 128
 129
 130 </PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
 131        <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>, <STRONG><A HREF="curs_getstr.3x.html">curs_getstr(3x)</A></STRONG>, <STRONG><A HREF="curs_printw.3x.html">curs_printw(3x)</A></STRONG>, <STRONG><A HREF="curs_termcap.3x.html">curs_termcap(3x)</A></STRONG>,
 132        <STRONG>scanf(3)</STRONG>.
 133
 134
 135
 136                                                                 <STRONG><A HREF="curs_scanw.3x.html">curs_scanw(3x)</A></STRONG>
 137 </PRE>
 138 <div class="nav">
 139 <ul>
 140 <li><a href="#h2-NAME">NAME</a></li>
 141 <li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li>
 142 <li><a href="#h2-DESCRIPTION">DESCRIPTION</a></li>
 143 <li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li>
 144 <li><a href="#h2-PORTABILITY">PORTABILITY</a></li>
 145 <li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>
 146 </ul>
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