Re: Win32::API and keyboard hook

[beech]

Hi,

Yup Win32::API docs are a bit confused

my $CallNextHookEx = Win32::API->Import( 'user32',
    'LRESULT WINAPI CallNextHookEx(HHOOK  hhk, int nCode, WPARAM wPara
+m, LPARAM lParam)'
);

Import creates sub CallNextHookEx (which you can call like CallNextHookEx() ), but the return value is a boolean, and you can't ->Call on it

If you want to be able to use $CallNextHookEx->Call() change Win32::API->Import to Win32::API->new

Also, MsgLoop will never get a chance to hear from sendString unless they run simultaneously, which means using two programs or using two threads ( MsgLoop runs in one thread, and sendString runs in another )

Good luck

[frazap]

Thanks for the correction.

Can someone show me how to use Win32::API::Struct ?

I have the C INPUT struct and I must send a pointer LPINPUT to that when calling SendInput.

If I understand the doc, I should say

Win32::API::Struct->typedef(
    *INPUT => qw(
        DWORD type;
        KEYBDINPUT    ki;
        )
);

But after that Win32::API::Type->is_known('LPINPUT') return false

How can I define the INPUT structure, put some data in it and then use that in the SendInput call ?

Thanks

[beech]

Hi,

https://metacpan.org/pod/Win32::API#USING-STRUCTURES gives some explanation about "LP" prefix

Here is a modified version of samples/GetCursorPos.pl

#!/usr/bin/perl --
use strict;
use warnings;
use Data::Dump qw/ dd /;
use Win32::API;

Win32::API::Struct->typedef(
    POINT => qw(
        LONG x;
        LONG y;
        )
);

Win32::API->Import('user32' => 'BOOL GetCursorPos(LPPOINT pt)');

#### using OO semantics
my $pt = Win32::API::Struct->new('POINT');
@{$pt}{qw/x y/} = (0,0);
GetCursorPos($pt) or die "GetCursorPos failed: $^E";
print "Cursor is at: $pt->{x}, $pt->{y}\n";

#### using tie semantics
my %pt;
tie %pt, 'Win32::API::Struct' => 'POINT';
@pt{qw/x y/}=(0,0);
GetCursorPos(\%pt) or die "GetCursorPos failed: $^E";
print "Cursor is at: $pt{x}, $pt{y}\n";

dd( map{ { "is_known $_ ", Win32::API::Type->is_known($_)}; } qw{ POIN
+T LPPOINT } );
__END__
Cursor is at: 198, 273
Cursor is at: 198, 273
({ "is_known POINT " => 1 }, { "is_known LPPOINT " => "" })

so POINT is know, but LPPOINT is not known, and that isn't a problem

[frazap]

Thanks !

The following code should use the SendInput to send abc to the keyboard. Windows responds that "The operation completed successfully."

However I don't see any abc in the console.

am I still wrong with the way I encode the character in the wScan field ?

Is this because I'm SendingInput in another thread ?

Here is the code

use strict;
use warnings;
use Data::Dumper;
use Win32::API;
use constant {
    KEYEVENTF_EXTENDEDKEY => 0x0001,
    KEYEVENTF_KEYUP       => 0x0002,
    KEYEVENTF_SCANCODE    => 0x0008,
    KEYEVENTF_UNICODE     => 0x0004,
    INPUT_KEYBOARD        => 1
};
Win32::API::Struct->typedef(
    KEYBDINPUT => qw(
        WORD      wVk;
        WORD      wScan;
        DWORD     dwFlags;
        DWORD     time;
        UINT_PTR dwExtraInfo;
        DWORD junk1;
        DWORD junk2;
        )
);

Win32::API::Struct->typedef(
    INPUT => qw(
        DWORD type;
        KEYBDINPUT    ki;
        )
);
#https://msdn.microsoft.com/en-us/library/windows/desktop/ms646310(v=v
+s.85).aspx
die("Error: $^E")
    unless (
    Win32::API::More->Import(
        'user32',
        'UINT WINAPI SendInput(UINT nInputs, LPINPUT pInputs, int cbSi
+ze)'
    )
    );

sub sendString {
    my $val = shift;
    my @val = split( //, $val );

    my @input = ( Win32::API::Struct->new("INPUT"),
        Win32::API::Struct->new("INPUT") );
    $input[0]->{type}          = INPUT_KEYBOARD;
    $input[0]->{ki}->{dwFlags} = KEYEVENTF_UNICODE;
    #$input[0]->{ki}->{dwFlags} = 0;
    $input[1]                  = $input[0];
    $input[1]->{ki}->{dwFlags} |= KEYEVENTF_KEYUP;

    for my $v (@val) {
        ( $input[0]->{ki}->{wVk},   $input[1]->{ki}->{wVk} )   = ( 0, 
+0 );
        ( $input[0]->{ki}->{junk1}, $input[1]->{ki}->{junk1} ) = ( 0, 
+0 );
        ( $input[0]->{ki}->{junk2}, $input[1]->{ki}->{junk2} ) = ( 0, 
+0 );
        ( $input[0]->{ki}->{time},  $input[1]->{ki}->{time} )  = ( 0, 
+0 );
        ( $input[0]->{ki}->{dwExtraInfo}, $input[1]->{ki}->{dwExtraInf
+o} ) =
            ( 0, 0 );
        my $code = ord($v);

        #A hardware scan code for the key. If dwFlags specifies KEYEVE
+NTF_UNICODE, 
        #wScan specifies a Unicode character which is to be sent to th
+e foreground application.
        print "$code\n";
        ( $input[0]->{ki}->{wScan}, $input[1]->{ki}->{wScan} ) = ( $co
+de, $code );

        for my $i ( 0 .. 1 ) {
           my $c = SendInput( 1, $input[$i], $input[$i]->sizeof );
           print "SendInput : $c\n";
            print  Win32::FormatMessage( Win32::GetLastError() );
        }
    }

}

sendString("abc");