ptk has asked for the wisdom of the Perl Monks concerning the following question:

Hi all,
Using the Win32::API lib, I want to import the following C function:
USHORT RscIoCheck
(ULONG ulConnectionHandle
,ULONG ulSessionHandle
,SHORT *pnIoHandle
,VOID *pvReplyBuffer
,USHORT *puReplySize
);

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which is found in the "Rscw32.dll". To import it, I have the following script:
use Win32::API 0.40;

my $sFuncRscIoCheck = new Win32::API('Rscw32', 'RSCCHK', 'IIPPP', 'I')
+;

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When I use it, I call the function as follow:
my $sReturn;
my $sIoHandle = RSC_IO_NOWAITED;
my $sCheckAll = RSC_IO_CHECK_ALL;
$sReturn = $sFuncRscIoCheck->Call($sConnectionHandle,
                                  $sSessionHandle,
                                  $sCheckAll,
                                  $sReplyBuffer,
                                  $sReplySize);

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I'm expecting a return value of '17' but when I print the "$sReturn", I got '33685510'.

If I do the following:
my $sReturn = pack('S', 0);

$sReturn = $sFuncRscIoCheck->Call($sConnectionHandle,
                                  $sSessionHandle,
                                  $sCheckAll,<br>
                                  $sReplyBuffer,
                                  $sReplySize);

$sReturn = unpack('S', $sReturn);

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print "My Return is : $sReturn\n";

the "$sReturn" value is set to '13107' and this value can (and probably will) change if I reboot the PC.
Is it possible to handle the USHORT correctly with the Win32::API lib?
Any idea?
Thanks,
ptk

Note: Even if the return value is incorrect, the function seems to work!

Edit by BazB: add code tags.

Replies are listed 'Best First'.
Re: Win32::API to import function
by esskar (Deacon) on Feb 28, 2005 at 20:38 UTC
    have you tried 
    my $sFuncRscIoCheck = new Win32::API('Rscw32', 'USHORT RscIoCheck(ULON
+G ulConnectionHandle,ULONG ulSessionHandle,SHORT *pnIoHandle,VOID *pv
+ReplyBuffer,USHORT *puReplySize)');

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    ?
[reply]
[d/l]
      If I use the following line to import the function:

      Win32::API->Import('Rscw32', 'USHORT RSCCHK(ULONG ulConnectionHandle,ULONG ulSessionHandle,SHORT *pnIoHandle,VOID *pvReplyBuffer,USHORT *puReplySize)');

      I have a crash at this line (i.e. as soon as I use it):

      $sReturn = RSCCHK($sConnectionHandle,
      $sSessionHandle,
      $sCheckAll,
      $sReplyBuffer,
      $sReplySize);

      Note: To import the "RscIoCheck" function, I need to use his API function name "RSCCHK".
[reply]
        I have try the "Import" and the following:

        my $sFuncRscIoCheck = new Win32::API('Rscw32', 'USHORT RSCCHK(ULONG ul
+ConnectionHandle,ULONG ulSessionHandle,SHORT *pnIoHandle,VOID *pvRepl
+yBuffer,USHORT *puReplySize)');

  $sReturn = $sFuncRscIoCheck->Call($sConnectionHandle,
                    $sSessionHandle,
                    $sCheckAll,
                    $sReplyBuffer,
                    $sReplySize);

        [download]

        They crash the perl interpreter with the Win error message: "Perl Command Line Interpreter has encountered a problem and needs to close. We are sorry for the inconvenience.".

        Any other idea?
[reply]
[d/l]

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