nf-winsock2-__wsafdisset.md

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NF:winsock2.__WSAFDIsSet	__WSAFDIsSet function (winsock2.h)	The __WSAFDIsSet function (winsock2.h) specifies whether a socket is included in a set of socket descriptors.	__WSAFDIsSet __WSAFDIsSet function [Winsock] winsock.wsafdisset winsock/__WSAFDIsSet	winsock\wsafdisset.htm	WinSock	ca420136-0b3b-45a1-85ce-83ab6ba1a70a	08/03/2022	__WSAFDIsSet, __WSAFDIsSet function [Winsock], winsock.wsafdisset, winsock/__WSAFDIsSet	winsock2.h	Winsock2.h	Windows	Windows 8.1, Windows Vista [desktop apps \| UWP apps]	Windows Server 2003 [desktop apps \| UWP apps]										Ws2_32.lib	Ws2_32.dll		Windows			19H1	__WSAFDIsSet winsock2/__WSAFDIsSet	c++	APIRef kbSyntax	DllExport	Ws2_32.dll	__WSAFDIsSet

-description

The __WSAFDIsSet function returns a value indicating whether a socket is included in a set of socket descriptors.

-parameters

-param fd

A file descriptor identifying a socket.

-param unnamedParam2

A pointer to an fd_set structure containing the set of socket descriptors.

-returns

Returns a non-zero value if the socket specified in fd is a member of the set specified in unnamedParam2. Otherwise, the function returns 0.

-remarks

Windows Phone 8: This function is supported for Windows Phone Store apps on Windows Phone 8 and later.

Windows 8.1 and Windows Server 2012 R2: This function is supported for Windows Store apps on Windows 8.1, Windows Server 2012 R2, and later.

The FD_ISSET macro expands to a call of function __WSAFDIsSet.

-see-also

• WSAAsyncSelect
• WSAEventSelect
• fd_set
• select