1accept(3XNET) X/Open Networking Services Library Functions accept(3XNET)
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6 accept - accept a new connection on a socket
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9 cc [ flag ... ] file ... -lxnet [ library ... ]
10 #include <sys/socket.h>
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13 int accept(int socket, struct sockaddr *restrict address,
14 socklen_t *restrict address_len);
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18 The accept() function extracts the first connection on the queue of
19 pending connections, creates a new socket with the same socket type
20 protocol and address family as the specified socket, and allocates a
21 new file descriptor for that socket.
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24 The function takes the following arguments:
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26 socket Specifies a socket that was created with socket(3XNET),
27 has been bound to an address with bind(3XNET), and has
28 issued a successful call to listen(3XNET).
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31 address Either a null pointer, or a pointer to a sockaddr struc‐
32 ture where the address of the connecting socket will be
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36 address_len Points to a socklen_t which on input specifies the
37 length of the supplied sockaddr structure, and on output
38 specifies the length of the stored address.
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42 If address is not a null pointer, the address of the peer for the
43 accepted connection is stored in the sockaddr structure pointed to by
44 address, and the length of this address is stored in the object pointed
45 to by address_len.
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48 If the actual length of the address is greater than the length of the
49 supplied sockaddr structure, the stored address will be truncated.
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52 If the protocol permits connections by unbound clients, and the peer is
53 not bound, then the value stored in the object pointed to by address is
54 unspecified.
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57 If the listen queue is empty of connection requests and O_NONBLOCK is
58 not set on the file descriptor for the socket, accept() will block
59 until a connection is present. If the listen(3XNET) queue is empty of
60 connection requests and O_NONBLOCK is set on the file descriptor for
61 the socket, accept() will fail and set errno to EAGAIN or EWOULDBLOCK.
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64 The accepted socket cannot itself accept more connections. The origi‐
65 nal socket remains open and can accept more connections.
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68 When a connection is available, select(3C) will indicate that the file
69 descriptor for the socket is ready for reading.
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72 Upon successful completion, accept() returns the nonnegative file
73 descriptor of the accepted socket. Otherwise, −1 is returned and errno
74 is set to indicate the error.
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77 The accept() function will fail if:
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79 EAGAIN O_NONBLOCK is set for the socket file descriptor and no
80 EWOULDBLOCK connections are present to be accepted.
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83 EBADF The socket argument is not a valid file descriptor.
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86 ECONNABORTED A connection has been aborted.
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89 EFAULT The address or address_len parameter can not be
90 accessed or written.
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93 EINTR The accept() function was interrupted by a signal that
94 was caught before a valid connection arrived.
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97 EINVAL The socket is not accepting connections.
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100 EMFILE OPEN_MAX file descriptors are currently open in the
101 calling process.
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104 ENFILE The maximum number of file descriptors in the system
105 are already open.
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108 ENOTSOCK The socket argument does not refer to a socket.
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111 EOPNOTSUPP The socket type of the specified socket does not sup‐
112 port accepting connections.
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116 The accept() function may fail if:
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118 ENOBUFS No buffer space is available.
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121 ENOMEM There was insufficient memory available to complete the
122 operation.
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125 ENOSR There was insufficient STREAMS resources available to com‐
126 plete the operation.
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129 EPROTO A protocol error has occurred; for example, the STREAMS pro‐
130 tocol stack has not been initialized.
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134 See attributes(5) for descriptions of the following attributes:
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139 ┌─────────────────────────────┬─────────────────────────────┐
140 │ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
141 ├─────────────────────────────┼─────────────────────────────┤
142 │Interface Stability │Standard │
143 ├─────────────────────────────┼─────────────────────────────┤
144 │MT-Level │MT-Safe │
145 └─────────────────────────────┴─────────────────────────────┘
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148 bind(3XNET), connect(3XNET), listen(3XNET), socket(3XNET),
149 attributes(5), standards(5)
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153SunOS 5.11 1 Nov 2003 accept(3XNET)