accept(2)							System Calls Manual							 accept(2)

NAME

       accept - Accepts a new connection on a socket

SYNOPSIS

       #include <sys/socket.h>

       int accept (	 int socket,	  struct sockaddr *address,	 socklen_t *address_len );

       [XNS4.0]  The definition of the accept() function in XNS4.0 uses a a size_t data type instead of socklen_t data type as specified in XNS5.0
       (the previous definition).

       [Tru64 UNIX]  The following definition of the accept() function does not conform to current standards and is supported  only  for  backward
       compatibility (see standards(5)):

       int accept (	 int socket,	  struct sockaddr *address,	 int *address_len );

STANDARDS

       Interfaces documented on this reference page conform to industry standards as follows:

       accept():  XNS5.0

       Refer to the standards(5) reference page for more information about industry standards and associated tags.

PARAMETERS

       Specifies  a file descriptor for the socket that was created with the socket() function, has been bound to an address with the bind() func-
       tion, and has issued a successful call to the listen() function.  Points to a sockaddr structure, the format of which is determined by  the
       domain  and  by	the  behavior requested for the socket.  The sockaddr structure is an overlay for a sockaddr_in, or sockaddr_un structure,
       depending on which of the supported address families is active.

	      [Tru64 UNIX]   If the compile-time option _SOCKADDR_LEN is defined before the sys/socket.h header file  is  included,  the  sockaddr
	      structure  takes 4.4BSD behavior, with a field for specifying the length of the socket address.  Otherwise, the default 4.3BSD sock-
	      addr structure is used, with the length of the socket address assumed to be 14 bytes or less.

	      You can specify NULL to indicate that the address of the peer is not required.

	      If _SOCKADDR_LEN is defined, the 4.3BSD sockaddr structure is defined with the name osockaddr.  Specifies the length of the sockaddr
	      structure pointed to by the address parameter.  If the address parameter is NULL then this parameter is ignored.

DESCRIPTION

       The  accept()  function extracts the first connection on the queue of pending connections, creates a new socket with the same properties as
       the specified socket, and allocates a new file descriptor for that socket.

       If the listen() queue is empty of connection requests, the accept() function blocks a calling socket of the blocking type until	a  connec-
       tion is present, or returns an [EWOULDBLOCK] for sockets marked nonblocking.

       The accepted socket cannot itself accept more connections.  The original socket remains open and can accept more connections.

NOTES

       [Tru64  UNIX]  When  compiled  in the X/Open UNIX environment or the POSIX.1g socket environment, calls to the accept() function are inter-
       nally renamed by prepending _E to the function name.  When you are debugging a module that includes the accept()  function  and	for  which
       _XOPEN_SOURCE_EXTENDED  or  _POSIX_PII_SOCKET  has  been defined, use _Eaccept to refer to the accept() call.  See standards(5) for further
       information.

RETURN VALUES

       Upon successful completion, the accept() function returns the nonnegative socket descriptor of the accepted socket.  Additionally,  if  the
       address	parameter  was	specified then it places the address of the peer in the sockaddr structure pointed to by the address, and sets the
       address_len parameter to the length of address.	If the accept() function fails, a value of -1 is returned and errno is set to indicate the
       error.

ERRORS

       If  the accept() function fails, errno may be set to one of the following values: The socket parameter is not valid.  A connection has been
       aborted.  The address parameter or address_len parameter is inaccessible or cannot be written.  The accept() function was interrupted by  a
       signal  that was caught before a valid connection arrived.  The socket is not accepting connections.  There are too many open file descrip-
       tors.  The maximum number of file descriptors in the system are already open.  Insufficient resources are available in the system  to  com-
       plete the call.	The system was unable to allocate kernel memory to increase the process descriptor table.  The available STREAMS resources
       were insufficient for the operation to complete.  The socket parameter refers to a file, not a socket.  The referenced socket cannot accept
       connections.  A protocol error occurred.  The socket is marked nonblocking, and no connections are present to be accepted.

RELATED INFORMATION

       Functions: bind(2), connect(2), listen(2), socket(2).

       Standards: standards(5).  delim off

																	 accept(2)