stack select() function doesn't work in Visual Studio - visual-studio-2010

Question

The following is part of the example code from http://curl.haxx.se/libcurl/c/sendrecv.html:
static int wait_on_socket(curl_socket_t sockfd, int for_recv, long timeout_ms)
{
struct timeval tv;
fd_set infd, outfd, errfd;
int res;
tv.tv_sec = timeout_ms / 1000;
tv.tv_usec= (timeout_ms % 1000) * 1000;
FD_ZERO(&infd);
FD_ZERO(&outfd);
FD_ZERO(&errfd);
FD_SET(sockfd, &errfd); /* always check for error */
if(for_recv)
{
FD_SET(sockfd, &infd);
}
else
{
FD_SET(sockfd, &outfd);
}
///* select() returns the number of signalled sockets or -1 */
res = select(sockfd + 1, &infd, &outfd, &errfd, &tv);
return res;
}
It worked fine on Linux, but when I brought it over Visual Studio 2010, it complains about the select() function. I compiled and linked all the cURL libraries/dlls correctly, and I even downloaded stuff as http request.
But when I tried to use the socket select() function, it complains with the following error:
error LNK2028: unresolved token (0A00034C) "extern "C" int __stdcall select(int,struct fd_set *,struct fd_set *,struct fd_set *,struct timeval const *)" (?select##$$J220YGHHPAUfd_set##00PBUtimeval###Z) referenced in function "int __cdecl `anonymous namespace'::wait_on_socket(unsigned int,int,long)" (?wait_on_socket#?A0x7d9db21b##$$FYAHIHJ#Z)
error LNK2019: unresolved external symbol "extern "C" int __stdcall select(int,struct fd_set *,struct fd_set *,struct fd_set *,struct timeval const *)" (?select##$$J220YGHHPAUfd_set##00PBUtimeval###Z) referenced in function "int __cdecl `anonymous namespace'::wait_on_socket(unsigned int,int,long)" (?wait_on_socket#?A0x7d9db21b##$$FYAHIHJ#Z)
Also, it seems that the select() function is compatible with Windows:
http://msdn.microsoft.com/en-us/library/ms740141(VS.85).aspx
Am I missing something? Can someone tell me how to get around this problem?
Thanks, --Rudy

Answer 1

You must link with the Microsoft socket library. Tell your linker to use Ws2_32.lib within your project.
In Visual Studio 2010 add this lib to Project->Properties->Linker->Input->Add. Dependencies.
Or add this lib inside your code with:
#pragma comment(lib, "Ws2_32.lib")