I never could get the "C type parser" of Win32::API to work. I always had more luck manually constructing the parameter string using the P and I chars, and then using unpack for strings passed in and out.

In your case, maybe the following construct works:

$function = Win32::API->new('NSLClientLibrary', 'XYZDecrypt', 'PPP', '
+I');

sub call_function {
    my ($value, $key, $encrypted) = @_;
    # Here we pad $value to the expected length, to avoid a buffer ove
+rrun
    # I guess that the result is at most as long as the encrypted stri
+ng
    $value = ' ' x length $encrypted;
    $function->( $value, $key, $encrypted );
    $value =~ s!\0.*!!; # we assume that the first \0 returned indicat
+es end of the string
    return $value
};

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In reply to Re: calling a function from a dll by Corion
in thread calling a function from a dll by nmeijer

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