Are you sure that your optical drives are SCSI? Because they are the only type that dll looks for. I tried it on my system (which uses IDE drives) and I get no errors, but no information (as you might expect).

#! perl -slw
use strict;
use Win32::API::Prototype;

ApiLink(
    'DiscIdCalcDLL', q[ int GetCdRomDrives( LPVOID p ) ],
) or die $^E;

my $struc = chr(0) x ( 4 + 1036*3 );

GetCdRomDrives( $struc ) or die $^E;

print "'$_'" for unpack 'v( VVV (a256)4 )3', $struc;

__END__
c:\test>DiskId.pl
'0'
'0'
'0'
'0'
'
'
'
'
'0'
'0'
'0'
'
'
'
'
'0'
'0'
'0'
'
'
'
'
[download]

However, you can query most everything about your system using DBD-WMI (though working out the right classnames can be a pain):

#! perl -slw
use strict;
use DBI;

my $dbh = DBI->connect('dbi:WMI:');

my $sth = $dbh->prepare(<<WQL);
SELECT  Caption, Name, Drive FROM  Win32_CDROMDrive
WQL

$sth->execute();
while( my @row = $sth->fetchrow ) {
    printf "Caption:  %25s Name:%30s Drive; %s\n", @row;
}

__END__
c:\test>junk
Caption:  HL-DT-ST CD-ROM GCR-8481B Name:  HL-DT-ST CD-ROM GCR-8481B D
+rive; R:
Caption:   LITE-ON DVDRW SOHW-1693S Name:   LITE-ON DVDRW SOHW-1693S D
+rive; D:
[download]

There are a whole bunch of other fields besides the 3 I've queried. They include:

Availability  
Capabilities  
CapabilityDescriptions  
Caption                    
CompressionMethod  
ConfigManagerErrorCode  
ConfigManagerUserConfig  
CreationClassName  
DefaultBlockSize  
Description   
DeviceID                                                              
+       
Drive  
DriveIntegrity  
ErrorCleared  
ErrorDescription  
ErrorMethodology  
FileSystemFlags  
FileSystemFlagsEx  
Id  
InstallDate  
LastErrorCode  
Manufacturer              
MaxBlockSize  
MaximumComponentLength  
MaxMediaSize  
MediaLoaded  
MediaType  
MfrAssignedRevisionLevel  
MinBlockSize  
Name                       
NeedsCleaning  
NumberOfMediaSupported  
PNPDeviceID                                                           
+       
PowerManagementCapabilities  
PowerManagementSupported  
RevisionLevel  
SCSIBus  
SCSILogicalUnit  
SCSIPort  
SCSITargetId  
Size        
Status  
StatusInfo  
SystemCreationClassName  
SystemName  
TransferRate  
VolumeName       
VolumeSerialNumber
[download]

I wanted to reply with full code, but I am missing the ASPI drivers and ... I am not going to mess with it :-).

A couple of observations:

1) You have already "told" "Win32::API" that your argument is a pointer (LP prefix) to a struct/record, hence you should just pass the perl scalar and not a reference to it. In other words, use this

"$x = GetCdRomDrives($cds);" 
instead of 
"$x = GetCdRomDrives(\$cds);"
[download]

2) If I understand the documentation correctly you must call the "$x = GetCdRomDrives($cds)" once and then loop through the results:

foreach $TCdRom (@{$cds->{TCdRom}}){
    printf("%s \n", $TCdRom->{HaId};
    ...
    ...
}
[download]

Of course I cannot check the code and expect some syntax issues/errors :-) YMMV.

CptSkripto

I thought they would be the same through ASPI, wouldn't they?

As far as I am aware, no. ASPI stands for the Advanced SCSI Programming Interface, so it seems unlikely.

Update: I'm wrong! According to wikipedia: Support for ATAPI interface (such as IDE) was later added.. (Shows how long it is since I did anything with ASPI! :)

However, the problem is that MS chose not to include an ASPI interface in XP/2000, so unless you've installed one yourself (such as the Adaptec freeware implementation), then using ASPI won't work.

Maybe his program uses other means to detect IDE optical drives?

---

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

"Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."

Yes, I do have ASPI installed (as a matter of fact, the "other function" that worked is the one that checks if ASPI is installed).

His software is very, very simple, I'd doubt he used other interface to IDE drives. But I think the code is all there, so I'll check it out anyway.

Thanks again!

VMat