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man pages section 3: Basic Library Functions

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Updated: Wednesday, July 27, 2022
 
 

bind (3C)

Name

bind - bind a name to a socket

Synopsis

#include <sys/socket.h>

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

Description

The bind() function assigns an address to an unnamed socket. Sockets created with socket(3C) function are initially unnamed. They are identified only by their address family.

The function takes the following arguments:

socket

Specifies the file descriptor of the socket to be bound.

address

Points to a sockaddr structure containing the address to be bound to the socket. The length and format of the address depend on the address family of the socket.

address_len

Specifies the length of the sockaddr structure pointed to by the address argument.

The socket in use may require the process to have appropriate privileges to use the bind() function.

Usage

An application program can retrieve the assigned socket name with the getsockname(3C) function.

The special value INADDR_ANY may be specified as the sin_addr field of the sockaddr_in structure as a wildcard value matching any IPv4 address on the local machine. For IPv6 sockets, the special value in6addr_any performs the same function when specified as the sin6_addr field of the sockaddr_in6 structure. See the inet(4P) and inet6(4P) manual pages for further details.

Return Values

Upon successful completion, bind() returns 0. Otherwise, −1 is returned and errno is set to indicate the error.

Errors

The bind() function will fail if:

EADDRINUSE

The specified address is already in use.

EADDRNOTAVAIL

The specified address is not available from the local machine.

EAFNOSUPPORT

The specified address is not a valid address for the address family of the specified socket, and the code was not built with __USE_SUNOS_SOCKETS__ defined as described in socket.h(3HEAD).

EBADF

The socket argument is not a valid file descriptor.

EFAULT

The address argument can not be accessed.

EINVAL

The socket is already bound to an address, and the protocol does not support binding to a new address; or the socket has been shut down.

ENOTSOCK

The socket argument does not refer to a socket.

EOPNOTSUPP

The socket type of the specified socket does not support binding to an address.

If the address family of the socket is AF_UNIX, then bind() will fail if:

EACCES

A component of the path prefix denies search permission, or the requested name requires writing in a directory with a mode that denies write permission.

EDESTADDRREQ
EISDIR

The address argument is a null pointer.

EIO

An I/O error occurred.

ELOOP

Too many symbolic links were encountered in translating the pathname in address.

ENAMETOOLONG

A component of a pathname exceeded NAME_MAX characters, or an entire pathname exceeded PATH_MAX characters.

ENOENT

A component of the pathname does not name an existing file or the pathname is an empty string.

ENOTDIR

A component of the path prefix of the pathname in address is not a directory.

EROFS

The name would reside on a read-only filesystem.

The bind() function may fail if:

EACCES

The specified address is protected, and the privilege {PRIV_NET_PRIVADDR} is not asserted in the effective set of the current process.

EINVAL

The address_len argument is not a valid length for the address family.

EISCONN

The socket is already connected.

ENAMETOOLONG

Pathname resolution of a symbolic link produced an intermediate result whose length exceeds PATH_MAX.

ENOBUFS

Insufficient resources were available to complete the call.

ENOSR

There were insufficient STREAMS resources for the operation to complete.

Attributes

See attributes(7) for descriptions of the following attributes:

ATTRIBUTE TYPE
ATTRIBUTE VALUE
Interface Stability
Committed
MT-Level
Async-Signal-Safe
Standard

See Also

connect(3C), getsockname(3C), listen(3C), remove(3C), socket(3C), socket.h(3HEAD), inet(4P), inet6(4P), attributes(7), privileges(7), standards(7)

Notes

Binding a name in the UNIX domain creates a socket in the file system that must be deleted by the caller when it is no longer needed by using remove(3C).

History

The bind() function has been present since the initial release of Solaris.