I have been able to get it to fully compile.
It croaks if OpenDevice returns a HANDLE, which is
typedef void* HANDLE;
But if OpenDevice returns void everything compiles and runs at least.
Here is the updated code:
package PIC::DevaSysI2CIO;
use strict;
use Inline C => Config =>
    LIBS => "-LE:/drivers/usb/devasys_i2cio -lusbi2cio",
    INC => "-IE:/drivers/usb/devasys_i2cio",
    BUILD_NOISY => 1;
use Inline C => q {
#include <windows.h>
#include "Usbi2cio.h"
#include <stdio.h>

void OpenDevice()
{
    HANDLE handle = INVALID_HANDLE_VALUE;
    
    handle = DAPI_OpenDeviceInstance("UsbI2cIo", 0);
    
    if (handle == INVALID_HANDLE_VALUE) {
        printf("Could not open device\n");
    }
    else {
        printf("Opened device!\n");
    }
}

};

sub new {
    my ($class_name) = @_;
    
    my ($self) = {};
    
    bless($self, $class_name);
    
    return $self;
}

sub open_device {
    OpenDevice();
}

1;

[download]

In reply to Re^2: Using Inline::C in a package by rem45acp
in thread Using Inline::C in a package by rem45acp

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