我的问题是在Windows 10机器上从GetWindowPlacement获取一个WINDOWPLACEMENT结构。我得到了一个有效的窗口句柄，并且创建该结构看起来不错，但是调用GetWindowPlacement失败。下面是我的代码：

#!/usr/bin/perl

use strict;
use warnings;
use Win32::API;

my $wpl; # WINDOWPLACEMENT structure 
my $hwnd;
my $rv;

Win32::API->Import("user32",   "FindWindow",         "PP",   "N");
Win32::API->Import("user32",   "GetWindowPlacement", "NP",   "I");

Win32::API::Struct->typedef( 'POINT', qw(
    LONG x; 
    LONG y; 
));
Win32::API::Struct->typedef( 'RECT', qw(
    LONG left;
    LONG top;
    LONG right;
    LONG bottom;
));
Win32::API::Struct->typedef( 'WINDOWPLACEMENT', qw(
    UINT  length;
    UINT  flags;
    UINT  showCmd;
    POINT ptMinPosition;
    POINT ptMaxPosition;
    RECT  rcNormalPosition;
    RECT  rcDevice;
));

$hwnd = FindWindow('SciCalc', 0);
print("window handle: $hwnd\n");

$wpl = Win32::API::Struct->new( 'WINDOWPLACEMENT' ); 
$wpl->{length} = Win32::API::Struct::sizeof($wpl);
print("pointer: $wpl\n");
print("length: $wpl->{length}\n");

$rv = GetWindowPlacement($hwnd, $wpl);
print("return value: $rv\n");

exit(0);

__END__

结果是：

window handle: 722532
pointer: Win32::API::Struct=HASH(0x2609b60)
length: 60
Win32::API::Call: parameter 2 had a buffer overflow at C:\Users\ma\MyFolder\test\winpos.pl line 41.

使用AutoIt 3获取WINDOWPLACEMENT结构会得到：
！[AutoIt 3结果] AutoIt3