Winsock Error Codes - Brought to you by Winsock-Error.com

10056 "Socket is already connected."

WSAEISCONN (Winsock error number: 10056)

Microsoft say this about Winsock error 10056 - WSAEISCONN:

A connect request was made on an already-connected socket. Some implementations also return this error if sendto is called on a connected SOCK_DGRAM socket (for SOCK_STREAM sockets, the to parameter in sendto is ignored) although other implementations treat this as a legal occurrence.

Full details of Winsock TCP error 10056 - WSAEISCONN:

Berkeley description: A connect request was made on an already connected socket; or, a or sendmsg() request on a connected socket specified a destination when already connected.

WinSock description: Same as Berkeley, except WinSock doesn't support the sendmsg() function, and some WinSock implementations are not so strict as to require an application with a datagram socket to "disconnect"--by calling with a AF_INET NULL destination address: INADDR_ANY (0.0.0.0), and port 0--before redirecting datagrams with or. On a datastream socket, some applications use this error with a non-blocking socket calling connect() to detect when a connection attempt has completed, although this is not recommended since some WinSocks fail with WSAEINVAL on subsequent calls.

   
This page is designed to help you to understand Winsock TCP error 10056. It will not necessarily mean you can instantly fix issues when your computer tells you that Winsock is having problems with code 10056, rather it will give you the necessary background information to help solve the matter.

Programming declarations for 10056 (WSAEISCONN):

C#
long WSAEISCONN = 10056 ;

VB.net
Dim WSAEISCONN As Long = 10056

VB6
Dim WSAEISCONN As Long
WSAEISCONN = 10056