Re^2: Call a function from DLL

Thank you for your suggestion

I just tried to use it but I got

"Can't call method "Call" without a package or object reference at script.pl line 9."

#!usr/bin/perl
use strict; 
use warnings;
use Win32::API;

my $function=Win32::API->Import(
'D:\Cleware\USBaccess.dll', 'int FCWInitObject()',
);
my $return = $function->Call();
[download]

Comment on Re^2: Call a function from DLL Download Code

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Re^3: Call a function from DLL by holli (Abbot) on Jul 15, 2019 at 11:19 UTC
I just downloaded the DLL from here and the following code works for me now. I noticed there are 32 and 64-Bit versions of the DLL. Make sure you are using the one that matches your Perl (64 bit most likely, find out by `perl -v`). use strict; use warnings; use Win32::API; my $FCWInitObject = Win32::API->Import( 'D:\ENV\USBaccess.dll', 'int FCWInitObject()', ); die "Error: ".( Win32::FormatMessage( Win32::GetLastError() ) ) if !$F +CWInitObject; my $FCWOpenCleware = Win32::API->Import( 'D:\ENV\USBaccess.dll', 'int FCWOpenCleware(int a)', ); die "Error: ".( Win32::FormatMessage( Win32::GetLastError() ) ) if !$F +CWOpenCleware; my $pointer = $FCWInitObject->Call(); print "Pointer $pointer\n"; my $success = $FCWOpenCleware->Call( $pointer ); print "Success $success\n"; [download] Works in the sense that it outputs the following and does not throw an error: `Pointer 8350080 Success 0` [download] That makes kinda sense since I don't have a device connected that could be "opened" but why does it then return a pointer in the first place? holli You can lead your users to water, but alas, you cannot drown them.	[reply] [d/l] [select]
Re^3: Call a function from DLL by holli (Abbot) on Jul 15, 2019 at 10:55 UTC
That's because your call to `Import` doesn't work. Apparently it returns an empty string. You should check for errors as Discipulus said above. holli You can lead your users to water, but alas, you cannot drown them.	[reply] [d/l] [select]