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<html>
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<body>
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<pre>
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NAME
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connect - initiate a connection on a socket
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SYNOPSIS
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#include <network.h>
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int connect(int sockfd, struct sockaddr *serv_addr, int
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addrlen);
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DESCRIPTION
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The parameter sockfd is a socket. If the socket is of
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type SOCK_DGRAM, this call specifies the peer with which
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the socket is to be associated; this address is that to
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which datagrams are to be sent, and the only address from
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which datagrams are to be received. If the socket is of
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type SOCK_STREAM, this call attempts to make a connection
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to another socket. The other socket is specified by
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serv_addr, which is an address in the communications space
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of the socket. Each communications space interprets the
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serv_addr parameter in its own way. Generally, stream
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sockets may successfully connect only once; datagram sock-
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ets may use connect multiple times to change their associ-
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ation. Datagram sockets may dissolve the association by
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connecting to an address with the sa_family sockaddr mem-
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ber set to AF_UNSPEC.
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RETURN VALUE
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If the connection or binding succeeds, zero is returned.
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On error, -1 is returned, and errno is set appropriately.
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ERRORS
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The following are general socket errors only. There may
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be other domain-specific error codes.
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EBADF Bad descriptor.
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ENOTSOCK
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The descriptor is not associated with a socket.
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EISCONN The socket is already connected.
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ECONNREFUSED
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Connection refused at server.
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ETIMEDOUT
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Timeout while attempting connection.
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ENETUNREACH
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Network is unreachable.
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EADDRINUSE
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Address is already in use.
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EINPROGRESS
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The socket is non-blocking and the connection can-
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not be completed immediately. It is possible to
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select(2) or poll(2) for completion by selecting
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the socket for writing. After select indicates
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writability, use getsockopt(2) to read the
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SO_ERROR option at level SOL_SOCKET to determine
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whether connect completed successfully (SO_ERROR
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is zero) or unsuccessfully (SO_ERROR is one of the
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usual error codes listed above, explaining the
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reason for the failure).
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EALREADY
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The socket is non-blocking and a previous connec-
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tion attempt has not yet been completed.
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EAFNOSUPPORT
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The passed address didn't have the correct address
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family in its sa_family field.
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EACCES The user tried to connect to a broadcast address
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without having the socket broadcast flag enabled.
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</pre>
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</body>
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</html>
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