accept – accept a new connection on a socket
cc [ flag ... ] file ... -lxnet [ library ... ]
#include <sys/socket.h>
int accept(int socket, struct sockaddr *address, socklen_t
*address_len);
The accept() function extracts the first connection on the queue of pending
connections, creates a new socket with the same socket type protocol and address
family as the specified socket, and allocates a new file descriptor for that socket.
The function takes the following arguments:
socket Specifies a socket that was created with socket(3XNET), has been
bound to an address with bind(3XNET), and has issued a
successful call to listen(3XNET).
address Either a null pointer, or a pointer to a sockaddr structure where
the address of the connecting socket will be returned.
address_len Points to a socklen_t which on input specifies the length of the
supplied sockaddr structure, and on output specifies the length
of the stored address.
If address is not a null pointer, the address of the peer for the accepted connection is
stored in the sockaddr structure pointed to by address, and the length of this address
is stored in the object pointed to by address_len.
If the actual length of the address is greater than the length of the supplied sockaddr
structure, the stored address will be truncated.
If the protocol permits connections by unbound clients, and the peer is not bound,
then the value stored in the object pointed to by address is unspecified.
If the listen queue is empty of connection requests and O_NONBLOCK is not set on
the file descriptor for the socket, accept() will block until a connection is present. If
the listen(3XNET) queue is empty of connection requests and O_NONBLOCK is set
on the file descriptor for the socket, accept() will fail and set errno to EAGAIN or
EWOULDBLOCK.
The accepted socket cannot itself accept more connections. The original socket remains
open and can accept more connections.
When a connection is available, select(3C) will indicate that the file descriptor for
the socket is ready for reading.
Upon successful completion, accept() returns the nonnegative file descriptor of the
accepted socket. Otherwise, −1 is returned and errno is set to indicate the error.
The accept() function will fail if:
accept(3XNET)
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20 man pages section 3: Networking Library Functions • Last Revised 8 May 1998