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Manual Reference Pages  - BIND (P)

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bind - bind a name to a socket

CONTENTS

Synopsis
Description
Return Value
Errors
Examples
Application Usage
Rationale
Future Directions
See Also
Copyright

#include <sys/socket.h>

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

The bind() function shall assign a local socket address address to a socket identified by descriptor socket that has no local socket address assigned. Sockets created with the socket() function are initially unnamed; they are identified only by their address family.

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

Upon successful completion, bind() shall return 0; otherwise, -1 shall be returned and errno set to indicate the error.

The bind() function shall 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.
EBADF	The socket argument is not a valid file descriptor.
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() shall 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 or EISDIR
	The address argument is a null pointer.
EIO	An I/O error occurred.
ELOOP	A loop exists in symbolic links encountered during resolution of 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 file system.
The bind() function may fail if:
EACCES	The specified address is protected and the current user does not have permission to bind to it.
EINVAL	The address_len argument is not a valid length for the address family.
EISCONN	The socket is already connected.
ELOOP	More than {SYMLOOP_MAX} symbolic links were encountered during resolution of the pathname in address.
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.

The following sections are informative.

None.

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

None.

None.

connect() , getsockname() , listen() , socket() , the Base Definitions volume of IEEE Std 1003.1-2001, <sys/socket.h>

Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .