BIND(2) BSD System Calls Manual BIND(2)
bind -- bind a name to a socket
bind(int s, const struct sockaddr *name, socklen_t namelen);
bind() assigns a name to an unnamed socket. When a socket is created
with socket(2) it exists in a name space (address family) but has no name
assigned. bind() requests that name be assigned to the socket. namelen
indicates the amount of space pointed to by name, in bytes.
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 (using
The rules used in name binding vary between communication domains. Con-
sult the manual entries in section 4 for detailed information.
Upon successful completion, the value 0 is returned; otherwise the
value -1 is returned and the global variable errno is set to indicate the
The bind() function will fail if:
[EBADF] s is not a valid descriptor.
[ENOTSOCK] s is not a socket.
[EADDRNOTAVAIL] The specified address is not available from the local
[EADDRINUSE] The specified address is already in use.
[EINVAL] The socket is already bound to an address, or namelen
is not a valid length for the supplied address.
[EAFNOSUPPORT] The family of the socket and that requested in
name->sa_family are not equivalent.
[ENOBUFS] Insufficient buffer space is available.
[EACCES] The requested address is protected, and the current
user has inadequate permission to access it.
[EFAULT] The name parameter is not in a valid part of the user
The following errors are specific to binding names in the UNIX-domain.
[ENOTDIR] A component of the path prefix is not a directory.
[ENAMETOOLONG] A component of a pathname exceeded NAME_MAX charac-
ters, or an entire pathname (including the terminating
NUL) exceeded PATH_MAX bytes.
[ENOENT] A prefix component of the path name does not exist.
[ELOOP] Too many symbolic links were encountered in translat-
ing the pathname.
[EIO] An I/O error occurred while making the directory entry
or allocating the inode.
[EROFS] The name would reside on a read-only file system.
[EISDIR] An empty pathname was specified.
connect(2), getsockname(2), listen(2), socket(2)
The bind() function conforms to IEEE Std 1003.1-2008 (``POSIX.1'').
The bind() system call first appeared in 4.1cBSD.
BSD March 28, 2017 BSD