I am working on a VB module that uses the SNMP API.
I am having problems now in translating the C declaration of an SNMP API
function.

The original C code:
--------------------

#define  RECVBUFSIZE    4096

//Type definitions

typedef SOCKET SockDesc;        // Socket is u_int in winsock.h, thats
long in VB

typedef struct _SNMP_MGR_SESSION {
    SockDesc  fd;
    struct  sockaddr  destAddr;            // sockaddr is from winsock.h

    LPSTR community;
    INT  timeout;
    INT  retries;
    AsnInteger  requestId;                    // is defined as LONG in C

    char  recvBuf[RECVBUFSIZE];

LPSNMP_MGR_SESSION
SNMP_FUNC_TYPE
SnmpMgrOpen(
    IN  LPSTR  lpAgentAddress,
    IN  LPSTR  lpAgentCommunity,
    IN  INT  nTimeOut,
    IN  INT  nRetries
    );

In a C sample program from the Platform SDK, the function is called like
this:

LPSNMP_MGR_SESSION  session;

session = SnmpMgrOpen(agent, community, timeout, retries)

That is my translation in VB:
----------------------------

Type sockaddr                    ' Taken from winsock.h
  sa_family As Integer          '/* address family */
  sa_data(14) As Byte           '/* up to 14 bytes of direct address */
End Type

Public Type Type_SNMP_MGR_SESSION
    fd As Long                                    ' Socket descriptor,
u_int in C
    destAddr As sockaddr
    community As String
    timeout As Long
    retries As Long
    requestId As Long
    recvBuf As String * 4096
End Type

'*************************************************
'**SNMP API Management Funktionen (MGMTAPI.DLL) **
'*************************************************
Declare Function SnmpMgrOpen Lib "mgmtapi.dll" _
                                 (ByVal lpAgentAddress As String, _
                                  ByVal lpAgentCommunity As String, _
                                  ByVal nTimeout As Long, _
                                  ByVal nRetries As Long) As
Type_SNMP_MGR_SESSION

My function call in VB:
-----------------------

Dim session As Type_SNMP_MGR_SESSION
Dim agent as String
Dim community as String
Dim timeout as Long
Dim retries as Long

session = SnmpMgrOpen(agent, community, timeout, retries)

This function call fails (wrong calling conventions). What is wrong with
my declaration?

Please help! I need it very urgently!

Andre

---------------------------
Andre Schneickert
ESCS, Germany