% perl -le"print $^E = 87"
The parameter is incorrect
[download]

So see ERROR_INVALID_PARAMETER in the docs, such as http://msdn.microsoft.com/en-us/library/windows/desktop/ms706613%28v=vs.85%29.aspx

I have a feeling that there's nothing obvious wrong with the values as such set in the perl application code. Under XP, it's mostly defaults that are available. Passing them on to the DLL seems to be the problem.

So, I'd likely next look at the guts of whatever that *Struct module ends up generating (probably via 'perl -d').

- tye        

The GUID is obtained the same way the stock Wlan::API does it and it is used all over the place, e.g in the (added by me) WlanSetProfile(), which creates a new profile from the required XML structures like thus:

sub WlanSetProfile {
    croak "Wlan functions are not available" unless $wlan_available;
    my ($handle, $guuid, $xmlref) = @_;
    my $reason = Zero;

    $API{ WlanSetProfile }->Call($handle, $guuid, 0, $$xmlref, 0, 1, 0
+, $reason) == 0
      or die "$^E";
};
[download]

Background: I want to automate establishing an ad-hoc network. On XP, insecure WEP is the only available encryption method. So, in order to make things a bit more secure, before connecting I create a new profile with a new WEP key, effectively creating a session key.

WlanSetProfile() succeeds and I can use the new profile to connect manually. So, the GUID is good. Also, the UTF16LE profilename is good, because before creating a new profile, I do some housekeeping and delete the previously used profile with the (added by me) WlanDeleteProfile()

sub WlanDeleteProfile  {
    croak "Wlan functions are not available" unless $wlan_available;
    my ($handle, $guuid, $profilename) = @_;
    $API{ WlanDeleteProfile }->Call($handle, $guuid, $profilename, 0) 
+== 0
      or die "$^E";
};
[download]

Deleting a profile works by supplying its name in the required fashion. WlanDeleteProfile() succeeds.

Unfortunately, using S for P in the signature

['WlanConnect' => 'IPSI' => 'I']

makes no difference.

I think my best bet is to follow Corion's suggestion and investigate pack()ing some string.

Can you post your whole modified Win32 Wlan module, or atleast api.pm, wlan.pm, and something that uses your WlanConnect? I'll obviously have to slightly modify it to work with my SSID. If its a bug with Win32::API I'm willing to fix it. Since the GUIDs are known to work, and aren't hard coded, I know they are fine.

Update: I decided to try and see if its a Win32::API or user problem in using Win32::API or a MS API problem. The following code, with the IPPI signature.
Read more... (4 kB)
generated

    hClientHandle    0x00000001    void *
+    pInterfaceGuid    0x00a55324 {04030201-0605-0807-0910-11121314151
+6}    const _GUID *
-    pConnectionParameters    0x00a21594 {wlanConnectionMode=862873943
+ strProfile=0x413a3a32 <Bad Ptr> pDot11Ssid=0x3a3a4950 {uSSIDLength=?
+?? ucSSID=0x3a3a4954 <Bad Ptr> } ...}    _WLAN_CONNECTION_PARAMETERS 
+* const
    wlanConnectionMode    862873943    _WLAN_CONNECTION_MODE
-    strProfile    0x413a3a32 <Bad Ptr>    const unsigned short *
        CXX0030: Error: expression cannot be evaluated    const unsign
+ed short
-    pDot11Ssid    0x3a3a4950 {uSSIDLength=??? ucSSID=0x3a3a4954 <Bad 
+Ptr> }    _DOT11_SSID *
    uSSIDLength    CXX0030: Error: expression cannot be evaluated    u
+nsigned long
+    ucSSID    0x3a3a4954 <Bad Ptr>    unsigned char [32]
-    pDesiredBssidList    0x75727453 {Header={Type=??? Revision=??? Si
+ze=??? } uNumOfEntries=??? uTotalNumOfEntries=??? ...}    DOT11_BSSID
+_LIST *
+    Header    {Type=??? Revision=??? Size=??? }    _NDIS_OBJECT_HEADE
+R
    uNumOfEntries    CXX0030: Error: expression cannot be evaluated   
+ unsigned long
    uTotalNumOfEntries    CXX0030: Error: expression cannot be evaluat
+ed    unsigned long
+    BSSIDs    0x7572745f    unsigned char [1][6]
    dot11BssType    1211987043    _DOT11_BSS_TYPE
    dwFlags    675828545    unsigned long
    pReserved    0x00000000    void *
[download]

in C. pConnectionParameters is gibberish, and its exactly what I thought it would be.

0x00A21594  57 69 6e 33 32 3a 3a 41 50 49 3a 3a 53 74 72 75 63 74 3d 4
+8 41 53 48 28 30 78 61 34 64  Win32::API::Struct=HASH(0xa4d
0x00A215B1  61 62 63 29 00 00 00 00 26 94 22 14 0d 02 00 00 00 ad ba a
+b ab ab ab ab ab ab ab ee 04  abc)....&”"......н║ллллллллю.
[download]

Now I changed the signature to IPSI, and, I don't know how you ran it, but Win32::API errored out and died on me.

Use of uninitialized value $type in string eq at C:/perl512/site/lib/W
+in32/API/S
truct.pm line 205.
Use of uninitialized value $type in pattern match (m//) at C:/perl512/
+site/lib/W
in32/API/Struct.pm line 216.
Use of uninitialized value $type in concatenation (.) or string at C:/
+perl512/si
te/lib/Win32/API/Struct.pm line 221.
Use of uninitialized value $type in string eq at C:/perl512/site/lib/W
+in32/API/S
truct.pm line 223.
Use of uninitialized value $name in hash element at C:/perl512/site/li
+b/Win32/AP
I/Struct.pm line 228.
Use of uninitialized value $self in string eq at C:/perl512/site/lib/W
+in32/API/T
ype.pm line 161.
Use of uninitialized value $type in exists at C:/perl512/site/lib/Win3
+2/API/Type
.pm line 167.
Use of uninitialized value $type in pattern match (m//) at C:/perl512/
+site/lib/W
in32/API/Type.pm line 173.
Use of uninitialized value $type in substitution (s///) at C:/perl512/
+site/lib/W
in32/API/Type.pm line 180.
Use of uninitialized value $type in exists at C:/perl512/site/lib/Win3
+2/API/Type
.pm line 182.
Use of uninitialized value $packing in pattern match (m//) at C:/perl5
+12/site/li
b/Win32/API/Type.pm line 142.
Use of uninitialized value $packing in hash element at C:/perl512/site
+/lib/Win32
/API/Type.pm line 146.
Use of uninitialized value $type_size in addition (+) at C:/perl512/si
+te/lib/Win
32/API/Struct.pm line 232.
Use of uninitialized value $type_size in modulus (%) at C:/perl512/sit
+e/lib/Win3
2/API/Struct.pm line 232.
Illegal modulus zero at C:/perl512/site/lib/Win32/API/Struct.pm line 2
+32.
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