VBA - Redis - Sockets - Low level TCP/IP code to interop with Redis

I'm going to show you some low level TCP/IP code to interoperate with Redis which is an open-source in-memory key-value store. Redis is a often used as a database cache to make cloud based applications more scalable by relieving the load on a relational database. I will give both C++ and VBA code that call a group of Win-32 Api functions known as Windows Sockets2 or Winsock.

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This post follows on from the previous post where I detailed (both in text and video) ...

1. How to install Redis
2. How to get some data into and out of Redis using the command line tool, redis-cli
3. How to call Redis from a VB.NET console application
4. How to call Redis from VBA via a VB.Net COM Dll Interop Assembly

This post shows a solution that skips the .NET component and instead scripts directly against the Windows Sockets 2 Api.

Background to Sockets - TCP/IP

Redis does not have an HTTP interface and so we have to drop down a few layers and program Sockets. If you are new to Sockets then here is a little explanation. When I say drop down a few layers, the diagram below is very useful. It illustrates the OSI model. When dealing with HTTP we deal with the top layer of the OSI model, the Application layer or layer 7. Programming sockets means programming the Transport layer or layer 4 of the OSI model. If you program a lower layer then you can expect the code to be more complicated (unless of course you are given a high level abstraction like .NET framework does).

Forewarned of the increased complexity let's look at some sample code.

Starting with C++

So Windows API functions (except .NET platform) are 99% designed to be used by C++ developers. Typically when reading a Windows API documentation page the sample code will be given in C++. It is a useful skill therefore to be able to get the C++ sample up running so that you can step through and understand the code. You are best trying to run a sample from the most recently updated documentation page. Any compile errors can be googled and, of course, stackoverflow.com is your friend.

The C++ sample I began with was the recv defined in winsock.h and housed in ws2_32.dll.

Sometimes you need to disable warnings so in the sample code for the recv function I needed to added the following line at the top

#pragma warning(disable:4996)   //https://stackoverflow.com/questions/36683785/inet-addr-use-inet-pton-or-inetpton-instead-or-define-winsock-deprecated/47397620

Here is the full C++ code for pasting into a Win32 C++ Console program

1. // Win32CppWinSockets2Play.cpp : This file contains the 'main' function. Program execution begins and ends there.
2. //
3.  
4. #include "pch.h"
5. #include <iostream>
6.  
7. #include <winsock2.h>
8. #include <Ws2tcpip.h>
9. #include <stdio.h>
10.  
11. // Link with ws2_32.lib
12. #pragma comment(lib, "Ws2_32.lib")
13.  
14. #define DEFAULT_BUFLEN 512
15. #define DEFAULT_PORT 6379
16.  
17. //#define _WINSOCK_DEPRECATED_NO_WARNINGS
18. #pragma warning(disable:4996)   //https://stackoverflow.com/questions/36683785/inet-addr-use-inet-pton-or-inetpton-instead-or-define-winsock-deprecated/47397620
19.  
20. int main()
21. {
22.         //----------------------
23.         // Declare and initialize variables.
24.         int iResult;
25.         WSADATA wsaData;
26.  
27.         SOCKET ConnectSocket = INVALID_SOCKET;
28.         struct sockaddr_in clientService;
29.  
30.         int recvbuflen = DEFAULT_BUFLEN;
31.         char *sendbuf = (char *)"keys *\r\n";
32.         char recvbuf[DEFAULT_BUFLEN] = "";
33.  
34.         //----------------------
35.         // Initialize Winsock
36.         iResult = WSAStartup(MAKEWORD(2, 2), &wsaData);
37.         if (iResult != NO_ERROR) {
38.                 wprintf(L"WSAStartup failed with error: %d\n", iResult);
39.                 return 1;
40.         }
41.  
42.         //----------------------
43.         // Create a SOCKET for connecting to server
44.         ConnectSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
45.         if (ConnectSocket == INVALID_SOCKET) {
46.                 wprintf(L"socket failed with error: %ld\n", WSAGetLastError());
47.                 WSACleanup();
48.                 return 1;
49.         }
50.  
51.         //----------------------
52.         // The sockaddr_in structure specifies the address family,
53.         // IP address, and port of the server to be connected to.
54.         clientService.sin_family = AF_INET;
55.  
56.         clientService.sin_addr.s_addr = inet_addr("127.0.0.1");
57.  
58.         clientService.sin_port = htons(DEFAULT_PORT);
59.  
60.         //----------------------
61.         // Connect to server.
62.         iResult = connect(ConnectSocket, (SOCKADDR*)&clientService, sizeof(clientService));
63.         if (iResult == SOCKET_ERROR) {
64.                 wprintf(L"connect failed with error: %d\n", WSAGetLastError());
65.                 closesocket(ConnectSocket);
66.                 WSACleanup();
67.                 return 1;
68.         }
69.  
70.         //----------------------
71.         // Send an initial buffer
72.         iResult = send(ConnectSocket, sendbuf, (int)strlen(sendbuf), 0);
73.         if (iResult == SOCKET_ERROR) {
74.                 wprintf(L"send failed with error: %d\n", WSAGetLastError());
75.                 closesocket(ConnectSocket);
76.                 WSACleanup();
77.                 return 1;
78.         }
79.  
80.         printf("Bytes Sent: %d\n", iResult);
81.  
82.         // shutdown the connection since no more data will be sent
83.         iResult = shutdown(ConnectSocket, SD_SEND);
84.         if (iResult == SOCKET_ERROR) {
85.                 wprintf(L"shutdown failed with error: %d\n", WSAGetLastError());
86.                 closesocket(ConnectSocket);
87.                 WSACleanup();
88.                 return 1;
89.         }
90.  
91.         // Receive until the peer closes the connection
92.         do {
93.  
94.                 iResult = recv(ConnectSocket, recvbuf, recvbuflen, 0);
95.                 if (iResult > 0)
96.                         wprintf(L"Bytes received: %d\n", iResult);
97.                 else if (iResult == 0)
98.                         wprintf(L"Connection closed\n");
99.                 else
100.                         wprintf(L"recv failed with error: %d\n", WSAGetLastError());
101.  
102.         } while (iResult > 0);
103.  
104.  
105.         // close the socket
106.         iResult = closesocket(ConnectSocket);
107.         if (iResult == SOCKET_ERROR) {
108.                 wprintf(L"close failed with error: %d\n", WSAGetLastError());
109.                 WSACleanup();
110.                 return 1;
111.         }
112.  
113.         WSACleanup();
114.         return 0;
115.     std::cout << "Hello World!\n"; 
116. }
117.  
118. // Run program: Ctrl + F5 or Debug > Start Without Debugging menu
119. // Debug program: F5 or Debug > Start Debugging menu
120.  
121. // Tips for Getting Started: 
122. //   1. Use the Solution Explorer window to add/manage files
123. //   2. Use the Team Explorer window to connect to source control
124. //   3. Use the Output window to see build output and other messages
125. //   4. Use the Error List window to view errors
126. //   5. Go to Project > Add New Item to create new code files, or Project > Add Existing Item to add existing code files to the project
127. //   6. In the future, to open this project again, go to File > Open > Project and select the .sln file
128.  

Transcribing from C++ to VBA

So Windows API functions are 99.9% designed to be used by C++ developers. VBA Developers must find function declarations with compatible signatures that match. for this Google is your friend but after a while one can get familiar with passing pointers by using VarPtr, StrPtr and ObjPtr.

1. Option Explicit
2. Option Private Module
3.  
4.  
5. 'reference Windows Sockets 2 - Windows applications _ Microsoft Docs
6. 'http://msdn.microsoft.com/en-us/library/windows/desktop/ms740673(v=vs.85).aspx
7. Private Const INVALID_SOCKET = -1
8. Private Const WSADESCRIPTION_LEN = 256
9. Private Const SOCKET_ERROR As Long = -1 'const #define SOCKET_ERROR            (-1)
10.  
11. Private Enum AF
12.     AF_UNSPEC = 0
13.     AF_INET = 2
14.     AF_IPX = 6
15.     AF_APPLETALK = 16
16.     AF_NETBIOS = 17
17.     AF_INET6 = 23
18.     AF_IRDA = 26
19.     AF_BTH = 32
20. End Enum
21.  
22. Private Enum sock_type
23.     SOCK_STREAM = 1
24.     SOCK_DGRAM = 2
25.     SOCK_RAW = 3
26.     SOCK_RDM = 4
27.     SOCK_SEQPACKET = 5
28. End Enum
29.  
30. Private Enum Protocol
31.     IPPROTO_ICMP = 1
32.     IPPROTO_IGMP = 2
33.     BTHPROTO_RFCOMM = 3
34.     IPPROTO_TCP = 6
35.     IPPROTO_UDP = 17
36.     IPPROTO_ICMPV6 = 58
37.     IPPROTO_RM = 113
38. End Enum
39.  
40. 'Private Type sockaddr
41. '    sa_family As Integer
42. '    sa_data(0 To 13) As Byte
43. 'End Type
44.  
45. Private Type sockaddr_in
46.     sin_family As Integer
47.     sin_port(0 To 1) As Byte
48.     sin_addr(0 To 3) As Byte
49.     sin_zero(0 To 7) As Byte
50. End Type
51.  
52.  
53. 'typedef UINT_PTR        SOCKET;
54. Private Type udtSOCKET
55.     pointer As Long
56. End Type
57.  
58.  
59.  
60. ' typedef struct WSAData {
61. '  WORD           wVersion;
62. '  WORD           wHighVersion;
63. '  char           szDescription[WSADESCRIPTION_LEN+1];
64. '  char           szSystemStatus[WSASYS_STATUS_LEN+1];
65. '  unsigned short iMaxSockets;
66. '  unsigned short iMaxUdpDg;
67. '  char FAR       *lpVendorInfo;
68. '} WSADATA, *LPWSADATA;
69.  
70. Private Type udtWSADATA
71.     wVersion As Integer
72.     wHighVersion As Integer
73.     szDescription(0 To WSADESCRIPTION_LEN) As Byte
74.     szSystemStatus(0 To WSADESCRIPTION_LEN) As Byte
75.     iMaxSockets As Integer
76.     iMaxUdpDg As Integer
77.     lpVendorInfo As Long
78. End Type
79.  
80. 'int errorno = WSAGetLastError()
81. Private Declare Function WSAGetLastError Lib "Ws2_32" () As Integer
82.  
83. '   int WSAStartup(
84. '  __in   WORD wVersionRequested,
85. '  __out  LPWSADATA lpWSAData
86. ');
87. Private Declare Function WSAStartup Lib "Ws2_32" _
88.     (ByVal wVersionRequested As Integer, ByRef lpWSAData As udtWSADATA) As winsockErrorCodes2
89.  
90.  
91. '    SOCKET WSAAPI socket(
92. '  __in  int af,
93. '  __in  int type,
94. '  __in  int protocol
95. ');
96.  
97. Private Declare Function ws2_socket Lib "Ws2_32" Alias "socket" _
98.     (ByVal AF As Long, ByVal stype As Long, ByVal Protocol As Long) As LongPtr
99.  
100. Private Declare Function ws2_closesocket Lib "Ws2_32" Alias "closesocket" _
101.     (ByVal socket As Long) As Long
102.  
103. 'int recv(
104. '  SOCKET s,
105. '  char   *buf,
106. '  int    len,
107. '  int    flags
108. ');
109. Private Declare Function ws2_recv Lib "Ws2_32" Alias "recv" _
110.     (ByVal socket As Long, ByVal buf As LongPtr, _
111.      ByVal length As Long, ByVal flags As Long) As Long
112.  
113. 'int WSAAPI connect(
114. '  SOCKET         s,
115. '  const sockaddr *name,
116. '  int            namelen
117. ');
118.  
119. Private Declare Function ws2_connect Lib "Ws2_32" Alias "connect" _
120.     (ByVal S As LongPtr, ByRef name As sockaddr_in, ByVal namelen As Long) As Long
121.  
122. 'int WSAAPI send(
123. '  SOCKET     s,
124. '  const char *buf,
125. '  int        len,
126. '  int        flags
127. ');
128. Private Declare Function ws2_send Lib "Ws2_32" Alias "send" _
129.     (ByVal S As LongPtr, ByVal buf As LongPtr, ByVal buflen As Long, ByVal flags As Long) As Long
130.  
131.  
132. Private Declare Function ws2_shutdown Lib "Ws2_32" Alias "shutdown" _
133.         (ByVal S As Long, ByVal how As Long) As Long
134.  
135. Private Declare Sub WSACleanup Lib "Ws2_32" ()
136.  
137. Private Enum eShutdownConstants
138.     SD_RECEIVE = 0  '#define SD_RECEIVE      0x00
139.     SD_SEND = 1     '#define SD_SEND         0x01
140.     SD_BOTH = 2     '#define SD_BOTH         0x02
141. End Enum
142.  
143. Private Sub TestWS2SendAndReceive()
144.  
145.     Dim sResponse As String
146.     If WS2SendAndReceive("KEYS *" & vbCrLf, sResponse) Then
147.         Debug.Print VBA.Join(RedisResponseToTypedVariable(sResponse), ";")
148.     End If
149.  
150.     If WS2SendAndReceive("GET foo" & vbCrLf, sResponse) Then
151.         Debug.Print RedisResponseToTypedVariable(sResponse)
152.     End If
153.  
154.     If WS2SendAndReceive("SET baz Barry" & vbCrLf, sResponse) Then
155.         Debug.Assert RedisResponseToTypedVariable(sResponse) = "OK"
156.     End If
157.  
158.     If WS2SendAndReceive("SET foo BAR" & vbCrLf, sResponse) Then
159.         Debug.Assert RedisResponseToTypedVariable(sResponse) = "OK"
160.     End If
161.  
162.     If WS2SendAndReceive("DEL baz" & vbCrLf, sResponse) Then
163.         Debug.Print RedisResponseToTypedVariable(sResponse)
164.     End If
165.  
166.  
167.     If WS2SendAndReceive("GET baz" & vbCrLf, sResponse) Then
168.         Debug.Print RedisResponseToTypedVariable(sResponse)
169.     End If
170.  
171.     If WS2SendAndReceive("GET foo" & vbCrLf, sResponse) Then
172.         Debug.Print RedisResponseToTypedVariable(sResponse)
173.     End If
174.  
175.  
176.     If WS2SendAndReceive("KEYS *" & vbCrLf, sResponse) Then
177.         Debug.Print VBA.Join(RedisResponseToTypedVariable(sResponse), ";")
178.     End If
179.  
180.  
181.     If WS2SendAndReceive("SET count 0" & vbCrLf, sResponse) Then
182.         Debug.Assert RedisResponseToTypedVariable(sResponse) = "OK"
183.     End If
184.  
185.     If WS2SendAndReceive("INCR count" & vbCrLf, sResponse) Then
186.         Debug.Assert RedisResponseToTypedVariable(sResponse) = "1"
187.     End If
188.  
189.  
190.  
191.  
192. End Sub
193.  
194. Public Function WS2SendAndReceive(ByVal sCommand As String, ByRef psResponse As String) As Boolean
195.     'https://docs.microsoft.com/en-gb/windows/desktop/api/winsock/nf-winsock-recv
196.  
197.     psResponse = ""
198.     '//----------------------
199.     '// Declare and initialize variables.
200.     Dim iResult As Integer : iResult = 0
201.     Dim wsaData As udtWSADATA
202.  
203.     Dim ConnectSocket As LongPtr
204.  
205.     Dim clientService As sockaddr_in
206.  
207.     Dim sendBuf() As Byte
208.     sendBuf = StrConv(sCommand, vbFromUnicode)
209.  
210.     Const recvbuflen As Long = 512
211.     Dim recvbuf(0 To recvbuflen - 1) As Byte
212.  
213.     '//----------------------
214.     '// Initialize Winsock
215.     Dim eResult As winsockErrorCodes2
216.     eResult = WSAStartup(&H202, wsaData)
217.     If eResult <> 0 Then
218.         Debug.Print "WSAStartup failed with error: " & eResult
219.         WS2SendAndReceive = False
220.         GoTo SingleExit
221.     End If
222.  
223.  
224.     '//----------------------
225.     '// Create a SOCKET for connecting to server
226.     ConnectSocket = ws2_socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)
227.     If ConnectSocket = INVALID_SOCKET Then
228.         Dim eLastError As winsockErrorCodes2
229.         eLastError = WSAGetLastError()
230.         Debug.Print "socket failed with error: " & eLastError
231.         Call WSACleanup
232.         WS2SendAndReceive = False
233.         GoTo SingleExit
234.     End If
235.  
236.  
237.     '//----------------------
238.     '// The sockaddr_in structure specifies the address family,
239.     '// IP address, and port of the server to be connected to.
240.     clientService.sin_family = AF_INET
241.  
242.     clientService.sin_addr(0) = 127
243.     clientService.sin_addr(1) = 0
244.     clientService.sin_addr(2) = 0
245.     clientService.sin_addr(3) = 1
246.  
247.     clientService.sin_port(1) = 235 '* 6379
248.     clientService.sin_port(0) = 24
249.  
250.     '//----------------------
251.     '// Connect to server.
252.  
253.     iResult = ws2_connect(ConnectSocket, clientService, LenB(clientService))
254.     If (iResult = SOCKET_ERROR) Then
255.  
256.         eLastError = WSAGetLastError()
257.  
258.         Debug.Print "connect failed with error: " & eLastError
259.         Call ws2_closesocket(ConnectSocket)
260.         Call WSACleanup
261.         WS2SendAndReceive = False
262.         GoTo SingleExit
263.     End If
264.  
265.     '//----------------------
266.     '// Send an initial buffer
267.     Dim sendbuflen As Long
268.     sendbuflen = UBound(sendBuf) - LBound(sendBuf) + 1
269.     iResult = ws2_send(ConnectSocket, VarPtr(sendBuf(0)), sendbuflen, 0)
270.     If (iResult = SOCKET_ERROR) Then
271.         eLastError = WSAGetLastError()
272.         Debug.Print "send failed with error: " & eLastError
273.  
274.         Call ws2_closesocket(ConnectSocket)
275.         Call WSACleanup
276.         WS2SendAndReceive = False
277.         GoTo SingleExit
278.     End If
279.  
280.     'Debug.Print "Bytes Sent: ", iResult
281.  
282.     '// shutdown the connection since no more data will be sent
283.     iResult = ws2_shutdown(ConnectSocket, SD_SEND)
284.     If (iResult = SOCKET_ERROR) Then
285.  
286.         eLastError = WSAGetLastError()
287.         Debug.Print "shutdown failed with error: " & eLastError
288.  
289.         Call ws2_closesocket(ConnectSocket)
290.         Call WSACleanup
291.         WS2SendAndReceive = False
292.         GoTo SingleExit
293.     End If
294.  
295.     ' receive only one message (TODO handle when buffer is not large enough)
296.  
297.     iResult = ws2_recv(ConnectSocket, VarPtr(recvbuf(0)), recvbuflen, 0)
298.     If (iResult > 0) Then
299.         'Debug.Print "Bytes received: ", iResult
300.     ElseIf (iResult = 0) Then
301.         Debug.Print "Connection closed"
302.         WS2SendAndReceive = False
303.         Call ws2_closesocket(ConnectSocket)
304.         Call WSACleanup
305.         GoTo SingleExit
306.     Else
307.         eLastError = WSAGetLastError()
308.         Debug.Print "recv failed with error: " & eLastError
309.     End If
310.  
311.     psResponse = Left$(StrConv(recvbuf, vbUnicode), iResult)
312.  
313.     'Debug.Print psResponse
314.  
315.     '// close the socket
316.     iResult = ws2_closesocket(ConnectSocket)
317.     If (iResult = SOCKET_ERROR) Then
318.  
319.         eLastError = WSAGetLastError()
320.         Debug.Print "close failed with error: " & eLastError
321.  
322.         Call WSACleanup
323.         WS2SendAndReceive = False
324.         GoTo SingleExit
325.     End If
326.  
327.     Call WSACleanup
328.     WS2SendAndReceive = True
329.  
330. SingleExit:
331.     Exit Function
332. ErrHand:
333.  
334. End Function
335.  
336. Public Function RedisResponseToTypedVariable(ByVal sResponse As String)
337.  
338.     Dim lTotalLength As Long
339.     lTotalLength = Len(sResponse)
340.     Debug.Assert lTotalLength > 0
341.  
342.     Dim vSplitResponse As Variant
343.     vSplitResponse = VBA.Split(sResponse, vbCrLf)
344.  
345.     Dim lReponseLineCount As Long
346.     lReponseLineCount = UBound(vSplitResponse) - LBound(vSplitResponse)
347.  
348.     Select Case Left(sResponse, 1)
349.         Case "$"
350.  
351.             RedisResponseToTypedVariable = vSplitResponse(1)
352.  
353.         Case "+"
354.             RedisResponseToTypedVariable = Mid$(vSplitResponse(0), 2)
355.  
356.         Case ":"
357.             '* response is an integer
358.             RedisResponseToTypedVariable = CLng(Mid$(vSplitResponse(0), 2))
359.  
360.         Case "-"
361.             '* response is an error
362.             Err.Raise vbObjectError, , Mid$(vSplitResponse(0), 2)
363.         'Stop
364.         Case "*"
365.             '* multiple responses, build an array to return
366.             Dim lResponseCount As Long
367.             lResponseCount = CLng(Mid$(vSplitResponse(0), 2))
368.             If lResponseCount > 0 Then
369.                 Debug.Assert lResponseCount = (lReponseLineCount - 1) / 2
370.         ReDim vReturn(0 To lResponseCount - 1)
371.                 Dim lLoop As Long
372.                 For lLoop = 0 To lResponseCount - 1
373.                     vReturn(lLoop) = vSplitResponse((lLoop + 1) * 2)
374.                 Next lLoop
375.             End If
376.             RedisResponseToTypedVariable = vReturn
377.  
378.         Case Else
379.             Stop  '* this should not happen
380.     End Select
381.  
382. End Function
383.  
384.  

Appendix A - Useful Enums

So it turned out I did not need these enumerations as such but I may in the future so parking here for safekeeping

modGlobalEnums Standard Module

1. Option Explicit
2.  
3. Public Enum sckState
4.     sckClosed = 0            ' Default. Closed
5.     sckOpen = 1              ' Open
6.     sckListening = 2         ' Listening
7.     sckConnectionPending = 3 ' Connection pending
8.     sckResolvingHost = 4     ' Resolving host
9.     sckHostResolved = 5      ' Host resolved
10.     sckConnecting = 6        ' Connecting
11.     sckConnected = 7         ' Connected
12.     sckClosing = 8           ' Peer is closing the connection
13.     sckError = 9             ' Error
14.  
15. End Enum
16.  
17. ''https://docs.microsoft.com/en-gb/windows/desktop/WinSock/windows-sockets-error-codes-2
18.  
19. Public Enum winsockErrorCodes2
20.     WSA_SUCCESS = 0
21.     WSA_INVALID_HANDLE = 6
22.     WSA_NOT_ENOUGH_MEMORY = 8
23.     WSA_INVALID_PARAMETER = 87
24.     WSA_OPERATION_ABORTED = 995
25.     WSA_IO_INCOMPLETE = 996
26.     WSA_IO_PENDING = 997
27.     WSA_E_INTR = 10004
28.     WSA_E_BADF = 10009
29.     WSA_E_ACCES = 10013
30.     WSA_E_FAULT = 10014
31.     WSA_E_INVAL = 10022
32.     WSA_E_MFILE = 10024
33.     WSA_E_WOULDBLOCK = 10035
34.     WSA_E_INPROGRESS = 10036
35.     WSA_E_ALREADY = 10037
36.     WSA_E_NOTSOCK = 10038
37.     WSA_E_DESTADDRREQ = 10039
38.     WSA_E_MSGSIZE = 10040         '* Message too long.
39.     WSA_E_PROTOTYPE = 10041
40.     WSA_E_NOPROTOOPT = 10042
41.     WSA_E_PROTONOSUPPORT = 10043
42.     WSA_E_SOCKTNOSUPPORT = 10044
43.     WSA_E_OPNOTSUPP = 10045
44.     WSA_E_PFNOSUPPORT = 10046
45.     WSA_E_AFNOSUPPORT = 10047
46.     WSA_E_ADDRINUSE = 10048
47.     WSA_E_ADDRNOTAVAIL = 10049
48.     WSA_E_NETDOWN = 10050
49.     WSA_E_NETUNREACH = 10051
50.     WSA_E_NETRESET = 10052
51.     WSA_E_CONNABORTED = 10053
52.     WSA_E_CONNRESET = 10054       '* Connection reset by peer.
53.     WSA_E_NOBUFS = 10055
54.     WSA_E_ISCONN = 10056
55.     WSA_E_NOTCONN = 10057
56.     WSA_E_SHUTDOWN = 10058
57.     WSA_E_TOOMANYREFS = 10059
58.     WSA_E_TIMEDOUT = 10060
59.     WSA_E_CONNREFUSED = 10061
60.     WSA_E_LOOP = 10062
61.     WSA_E_NAMETOOLONG = 10063
62.     WSA_E_HOSTDOWN = 10064
63.     WSA_E_HOSTUNREACH = 10065
64.     WSA_E_NOTEMPTY = 10066
65.     WSA_E_PROCLIM = 10067
66.     WSA_E_USERS = 10068
67.     WSA_E_DQUOT = 10069
68.     WSA_E_STALE = 10070
69.     WSA_E_REMOTE = 10071
70.     WSASYSNOTREADY = 10091
71.     WSAVERNOTSUPPORTED = 10092
72.     WSANOTINITIALISED = 10093
73.     WSA_E_DISCON = 10101
74.     WSA_E_NOMORE = 10102
75.     WSA_E_CANCELLED = 10103
76.     WSA_E_INVALIDPROCTABLE = 10104
77.     WSA_E_INVALIDPROVIDER = 10105
78.     WSA_E_PROVIDERFAILEDINIT = 10106
79.     WSASYSCALLFAILURE = 10107
80.     WSASERVICE_NOT_FOUND = 10108
81.     WSATYPE_NOT_FOUND = 10109
82.     WSA_E_NO_MORE = 10110
83.     WSA_E_CANCELLED_2 = 10111
84.     WSA_E_REFUSED = 10112
85.     WSAHOST_NOT_FOUND = 11001
86.     WSATRY_AGAIN = 11002
87.     WSANO_RECOVERY = 11003
88.     WSANO_DATA = 11004
89.     WSA_QOS_RECEIVERS = 11005
90.     WSA_QOS_SENDERS = 11006
91.     WSA_QOS_NO_SENDERS = 11007
92.     WSA_QOS_NO_RECEIVERS = 11008
93.     WSA_QOS_REQUEST_CONFIRMED = 11009
94.     WSA_QOS_ADMISSION_FAILURE = 11010
95.     WSA_QOS_POLICY_FAILURE = 11011
96.     WSA_QOS_BAD_STYLE = 11012
97.     WSA_QOS_BAD_OBJECT = 11013
98.     WSA_QOS_TRAFFIC_CTRL_ERROR = 11014
99.     WSA_QOS_GENERIC_ERROR = 11015
100.     WSA_QOS_ESERVICETYPE = 11016
101.     WSA_QOS_EFLOWSPEC = 11017
102.     WSA_QOS_EPROVSPECBUF = 11018
103.     WSA_QOS_EFILTERSTYLE = 11019
104.     WSA_QOS_EFILTERTYPE = 11020
105.     WSA_QOS_EFILTERCOUNT = 11021
106.     WSA_QOS_EOBJLENGTH = 11022
107.     WSA_QOS_EFLOWCOUNT = 11023
108.     WSA_QOS_EUNKOWNPSOBJ = 11024
109.     WSA_QOS_EPOLICYOBJ = 11025
110.     WSA_QOS_EFLOWDESC = 11026
111.     WSA_QOS_EPSFLOWSPEC = 11027
112.     WSA_QOS_EPSFILTERSPEC = 11028
113.     WSA_QOS_ESDMODEOBJ = 11029
114.     WSA_QOS_ESHAPERATEOBJ = 11030
115.     WSA_QOS_RESERVED_PETYPE = 11031
116. End Enum