Re: IActiveDesktop::SetWallpaper from Perl?

[Mr. Muskrat]

#!/usr/bin/perl
use strict;
use warnings;
use Win32::API;
use constant CLSID_ACTIVEDESKTOP   => '{75048700-EF1F-11D0-9888-006097
+DEACF9}';
my $coci = Win32::API->new('ole32','CoCreateInstance', [qw(I P I I P)]
+, 'I')
  or die "Could not create CoCreateInstance object";
my $setwall;
my $res = $coci->Call(CLSID_ACTIVEDESKTOP, undef, 0, 0, \$setwall);
print "Got: $res\n";

Errors returned:

Argument "{75048700-EF1F-11D0-9888-006097DEACF9}" isn't numeric in sub
+routine entry at noname.pl line 11.
Use of uninitialized value in subroutine entry at noname.pl line 11.

And it outputs:

Got: -2147024809

 

Update: Fixed the die message in my code

Edit by tye to change PRE to CODE tags around long lines

[blm]

IMHO you are getting that error message because the first parameter of

STDAPI CoCreateInstance(
    REFCLSID rclsid,
    LPUNKNOWN pUnkOuter,
    DWORD dwClsContext,
    REFIID riid,
    LPVOID * ppv
);

is a struct not a string

typedef struct _GUID {          // size is 16
    DWORD Data1;
    WORD   Data2;
    WORD   Data3;
    BYTE  Data4[8];
} GUID;

defined on my machine in WINNT.H

--blm--

[Mr. Muskrat]

Thanks. I don't play with the system calls too often. I was using the code that bbfu provided. I didn't know if it was correct or not. Perhaps I'll have time to play with this more later in the week. It's becoming quite fun.