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CONNECT(2)                FreeBSD System Calls Manual               CONNECT(2)

     connect -- initiate a connection on a socket

     Standard C Library (libc, -lc)

     #include <sys/types.h>
     #include <sys/socket.h>

     connect(int s, const struct sockaddr *name, socklen_t namelen);

     The parameter s is a socket.  If it is of type SOCK_DGRAM, this call
     specifies the peer with which the socket is to be associated; this
     address is that to which datagrams are to be sent, and the only address
     from which datagrams are to be received.  If the socket is of type
     SOCK_STREAM, this call attempts to make a connection to another socket.
     The other socket is specified by name, which is an address in the commu-
     nications space of the socket.  Each communications space interprets the
     name parameter in its own way.  Generally, stream sockets may success-
     fully connect() only once; datagram sockets may use connect() multiple
     times to change their association.  Datagram sockets may dissolve the
     association by connecting to an invalid address, such as a null address.

     The connect() function returns the value 0 if successful; otherwise the
     value -1 is returned and the global variable errno is set to indicate the

     The connect() call fails if:

     [EBADF]            s is not a valid descriptor.

     [ENOTSOCK]         s is a descriptor for a file, not a socket.

     [EADDRNOTAVAIL]    The specified address is not available on this

     [EAFNOSUPPORT]     Addresses in the specified address family cannot be
                        used with this socket.

     [EISCONN]          The socket is already connected.

     [ETIMEDOUT]        Connection establishment timed out without establish-
                        ing a connection.

     [ECONNREFUSED]     The attempt to connect was forcefully rejected.

     [ENETUNREACH]      The network is not reachable from this host.

     [EHOSTUNREACH]     The remote host is not reachable from this host.

     [EADDRINUSE]       The address is already in use.

     [EFAULT]           The name parameter specifies an area outside the
                        process address space.

     [EINPROGRESS]      The socket is non-blocking and the connection cannot
                        be completed immediately.  It is possible to select(2)
                        for completion by selecting the socket for writing.

     [EALREADY]         The socket is non-blocking and a previous connection
                        attempt has not yet been completed.

     [EACCES]           An attempt is made to connect to a broadcast address
                        (obtained through the INADDR_BROADCAST constant or the
                        INADDR_NONE return value) through a socket that does
                        not provide broadcast functionality.

     The following errors are specific to connecting names in the UNIX domain.
     These errors may not apply in future versions of the UNIX IPC domain.

     [ENOTDIR]          A component of the path prefix is not a directory.

     [ENAMETOOLONG]     A component of a pathname exceeded 255 characters, or
                        an entire path name exceeded 1023 characters.

     [ENOENT]           The named socket does not exist.

     [EACCES]           Search permission is denied for a component of the
                        path prefix.

     [EACCES]           Write access to the named socket is denied.

     [ELOOP]            Too many symbolic links were encountered in translat-
                        ing the pathname.

     accept(2), getpeername(2), getsockname(2), select(2), socket(2)

     The connect() function call appeared in 4.2BSD.

FreeBSD 4.10                     June 4, 1993                     FreeBSD 4.10


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