This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface

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

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard
       for Information  Technology  --  Portable  Operating  System  Interface  (POSIX),  The  Open  Group  Base
       Specifications  Issue  7, 2018 Edition, Copyright (C) 2018 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 .

       Any  typographical  or formatting errors that appear in this page are most likely to have been introduced
       during  the  conversion  of  the  source  files  to  man  page  format.  To  report  such   errors,   see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                                   2017                                          BIND(3POSIX)

       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.

       If  the address family of the socket is AF_UNIX and the pathname in address names a symbolic link, bind()
       shall fail and set errno to [EADDRINUSE].

       If the socket address cannot be assigned immediately and O_NONBLOCK is set for the  file  descriptor  for
       the  socket,  bind()  shall  fail and set errno to [EINPROGRESS], but the assignment request shall not be
       aborted, and the assignment shall be completed asynchronously. Subsequent calls to bind()  for  the  same
       socket, before the assignment is completed, shall fail and set errno to [EALREADY].

       When  the  assignment  has  been performed asynchronously, pselect(), select(), and poll() shall indicate
       that the file descriptor for the socket is ready for reading and writing.

       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.

       EALREADY
              An assignment request is already in progress for the specified socket.

       EBADF  The socket argument is not a valid file descriptor.

       EINPROGRESS
              O_NONBLOCK  is set for the file descriptor for the socket and the assignment cannot be immediately
              performed; the assignment shall be performed asynchronously.

       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.

       ENOBUFS
              Insufficient resources were available to complete the call.

       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
              The length of a component of a pathname is longer than {NAME_MAX}.

       ENOENT A  component  of  the path prefix of the pathname in address does not name an existing file or the
              pathname is an empty string.

       ENOENT or ENOTDIR
              The pathname in address contains at least one non-<slash> character and  ends  with  one  or  more
              trailing <slash> characters. If the pathname without the trailing <slash> characters would name an
              existing file, an [ENOENT] error shall not occur.

       ENOTDIR
              A component of the path prefix of the pathname in address names an existing file that is neither a
              directory  nor  a  symbolic  link to a directory, or the pathname in address contains at least one
              non-<slash> character and ends with one or more trailing <slash> characters and the last  pathname
              component names an existing file that is neither a directory nor a symbolic link to 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
              The length of a pathname exceeds {PATH_MAX}, or pathname resolution of a symbolic link produced an
              intermediate result with a length that exceeds {PATH_MAX}.

       Thefollowingsectionsareinformative.

       The following code segment shows how to create a socket and bind it to a name in the AF_UNIX domain.

           #define MY_SOCK_PATH "/somepath"

           int sfd;
           struct sockaddr_un my_addr;

           sfd = socket(AF_UNIX, SOCK_STREAM, 0);
           if (sfd == -1)
               /* Handle error */;

           memset(&my_addr, '\0', sizeof(struct sockaddr_un));
                                /* Clear structure */
           my_addr.sun_family = AF_UNIX;
           strncpy(my_addr.sun_path, MY_SOCK_PATH, sizeof(my_addr.sun_path) -1);

           if (bind(sfd, (struct sockaddr *) &my_addr,
               sizeof(struct sockaddr_un)) == -1)
               /* Handle error */;

       None.

       bind — bind a name to a socket

       This  manual  page  is part of the POSIX Programmer's Manual.  The Linux implementation of this interface
       may differ (consult the corresponding Linux manual page for details of Linux behavior), or the  interface
       may not be implemented on Linux.

       None.

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

connect(), getsockname(), listen(), socket()

       The Base Definitions volume of POSIX.1‐2017, <sys_socket.h>

       #include <sys/socket.h>

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