accept(3N)                                                       accept(3N)


   NAME
         accept - accept a connection on a socket

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

         ns = accept(s, addr, addrlen)
         int ns, s;
         struct sockaddr *addr;
         int *addrlen;

   DESCRIPTION
         The argument s is a socket that has been created with socket(3N) and
         bound to an address with bind(3N), and that is listening for
         connections after a call to listen(3N).  accept() extracts the first
         connection on the queue of pending connections, creates a new socket
         with the properties of s, and allocates a new file descriptor, ns,
         for the socket.  If no pending connections are present on the queue
         and the socket is not marked as non-blocking, accept() blocks the
         caller until a connection is present.  If the socket is marked as
         non-blocking and no pending connections are present on the queue,
         accept() returns an error as described below.  accept() uses the
         netconfig(4) file to determine the STREAMS device file name
         associated with s. This is the device on which the connect indication
         will be accepted.  The accepted socket, ns, is used to read and write
         data to and from the socket that connected to ns; it is not used to
         accept more connections.  The original socket (s) remains open for
         accepting further connections.

         The argument addr is a result parameter that is filled in with the
         address of the connecting entity as it is known to the communications
         layer.  The exact format of the addr parameter is determined by the
         domain in which the communication occurs.

         addrlen is a value-result parameter.  Initially, it contains the
         amount of space pointed to by addr; on return it contains the length
         in bytes of the address returned.

         accept() is used with connection-based socket types, currently with
         SOCK_STREAM.

         It is possible to select(3N) a socket for the purpose of an accept()
         by selecting it for read.  However, this will only indicate when a
         connect indication is pending; it is still necessary to call
         accept().

   RETURN VALUE
         accept() returns -1 on error.  If it succeeds, it returns a non-
         negative integer that is a descriptor for the accepted socket.



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   accept(3N)                                                       accept(3N)


   ERRORS
         accept() will fail if:

         EBADF               The descriptor is invalid.

         ENOTSOCK            The descriptor does not reference a socket.

         EOPNOTSUPP          The referenced socket is not of type SOCK_STREAM.

         EWOULDBLOCK         The socket is marked as non-blocking and no
                             connections are present to be accepted.

         EPROTO              A protocol error has occurred; for example, the
                             STREAMS protocol stack has not been initialized.

         ENODEV              The protocol family and type corresponding to s
                             could not be found in the netconfig file.

         ENOMEM              There was insufficient user memory available to
                             complete the operation.

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

   SEE ALSO
         bind(3N), connect(3N), listen(3N), socket(3N), netconfig(4).



























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