ACCEPT(2)ACCEPT(2)NAMEaccept - 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(2), bound
to an address with bind(2), and is listening for connections after a
listen(2). Accept extracts the first connection on the queue of
pending connections, creates a new socket with the same 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 non-blocking and no pending connections are
present on the queue, accept returns an error as described below. The
accepted socket, ns, may not be used to accept more connections. The
original socket s remains open.
The argument addr is a result parameter that is filled in with the
address of the connecting entity, as known to the communications layer.
The exact format of the addr parameter is determined by the domain in
which the communication is occurring. The addrlen is a value-result
parameter; it should initially contain the amount of space pointed to
by addr; on return it will contain the actual length (in bytes) of the
address returned. This call is used with connection-based socket
types, currently with SOCK_STREAM.
It is possible to select(2) a socket for the purposes of doing an
accept by selecting it for read.
RETURN VALUE
The call returns -1 on error. If it succeeds, it returns a non-
negative integer that is a descriptor for the accepted socket.
ERRORS
The accept will fail if:
[EBADF] The descriptor is invalid.
[ENOTSOCK] The descriptor references a file, not a socket.
[EOPNOTSUPP] The referenced socket is not of type SOCK_STREAM.
[EFAULT] The addr parameter is not in a writable part of the
user address space.
[EWOULDBLOCK] The socket is marked non-blocking and no
connections are present to be accepted.
SEE ALSObind(2), connect(2), listen(2), select(2), socket(2)4.2 Berkeley Distribution May 22, 1986 ACCEPT(2)