connect(3N)                      UNIX System V                      connect(3N)


NAME
      connect - initiate a connection on a socket

SYNOPSIS
      #include <sys/types.h>

      int connect(int s, addrt name, int namelen);

DESCRIPTION
      The parameter s is a socket.  If it is of type SOCKDGRAM, connect
      specifies the peer with which the socket is to be associated; this
      address is the address to which datagrams are to be sent if a receiver is
      not explicitly designated; it is the only address from which datagrams
      are to be received.  If the socket s is of type SOCKSTREAM, connect
      attempts to make a connection to another socket.  The other socket is
      specified by name.  name is an address in the communications space of the
      socket.  Each communications space interprets the name parameter in its
      own way.  If s is not bound, then it will be bound to an address selected
      by the underlying transport provider.  Generally, stream sockets may
      successfully connect only once; datagram sockets may use connect multiple
      times to change their association.  Datagram sockets may dissolve the
      association by connecting to a null address.

RETURN VALUE
      If the connection or binding succeeds, then 0 is returned.  Otherwise a
      -1 is returned and a more specific error code is stored in errno.

ERRORS
      The call fails if:

      EBADF               s is not a valid descriptor.

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

      EINVAL              namelen is not the size of a valid address for the
                          specified address family.

      EADDRNOTAVAIL       The specified address is not available on the remote
                          machine.

      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
                          establishing a connection.

      ECONNREFUSED        The attempt to connect was forcefully rejected.  The
                          calling program should close the socket descriptor,
                          and issue another socket call to obtain a new
                          descriptor before attempting another connect call.


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connect(3N)                      UNIX System V                      connect(3N)


      ENETUNREACH         The network is not reachable from this host.

      EADDRINUSE          The address is already in use.

      EINPROGRESS         The socket is non-blocking and the connection cannot
                          be completed immediately.  It is possible to select
                          for completion by selecting the socket for writing.
                          However, this is only possible if the socket STREAMS
                          module is the topmost module on the protocol stack
                          with a write service procedure.  This will be the
                          normal case.

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

      EINTR               The connection attempt was interrupted before any
                          data arrived by the delivery of a signal.

      ENOTSOCK            The file referred to by name is not a socket.

      EPROTOTYPE          The file referred to by name is a socket of a type
                          other than type s (for example, s is a SOCKDGRAM
                          socket, while name refers to a SOCKSTREAM socket).

      ENOSR               There were insufficient STREAMS resources available
                          to complete the operation.

      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 of the pathname in
                          name is not a directory.

      ENOENT              A component of the path prefix of the pathname in
                          name does not exist.

      ENOENT              The socket referred to by the pathname in name does
                          not exist.

      EACCES              Search permission is denied for a component of the
                          path prefix of the pathname in name.

      ELOOP               Too many symbolic links were encountered in
                          translating the pathname in name.

      EIO                 An I/O error occurred while reading from or writing
                          to the file system.

SEE ALSO
      accept(3N), connect(3N), getsockname(3N), socket(3N).
      close(2) in the Programmer's Reference Manual.



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connect(3N)                      UNIX System V                      connect(3N)


NOTES
      The type of address structure passed to connect depends on the address
      family.  UNIX domain sockets (address family AFUNIX) require a
      socketaddrun structure as defined in sys/un.h; Internet domain sockets
      (address family AFINET) require a sockaddrin structure as defined in
      netinet/in.h.  Other address families may require other structures.  Use
      the structure appropriate to the address family; cast the structure
      address to a generic caddrt in the call to connect and pass the size of
      the structure in the namelen argument.













































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