NAME

       io_uring_prep_socket - prepare a socket creation request

SYNOPSIS

       #include <sys/socket.h>
       #include <liburing.h>

       void io_uring_prep_socket(struct io_uring_sqe *sqe,
                                 int domain,
                                 int type,
                                 int protocol,
                                 unsigned int flags);

       void io_uring_prep_socket_direct(struct io_uring_sqe *sqe,
                                        int domain,
                                        int type,
                                        int protocol,
                                        unsigned int file_index,
                                        unsigned int flags);

       void io_uring_prep_socket_direct_alloc(struct io_uring_sqe *sqe,
                                        int domain,
                                        int type,
                                        int protocol,
                                        unsigned int flags);

DESCRIPTION

       The  io_uring_prep_socket(3)  function  prepares a socket creation request. The submission
       queue entry sqe is setup to use the communication domain defined by  domain  and  use  the
       communication  type  defined by type and the protocol set by protocol.  The flags argument
       are currently unused.

       The io_uring_prep_socket_direct(3) helper works just like io_uring_prep_socket(3),  except
       it maps the socket to a direct descriptor rather than return a normal file descriptor. The
       file_index argument should be set to the slot that should be used for this socket.

       The      io_uring_prep_socket_direct_alloc(3)      helper      works       just       like
       io_uring_prep_socket_alloc(3),  except  it  allocates  a new direct descriptor rather than
       pass a free slot  in.  It  is  equivalent  to  using  io_uring_prep_socket_direct(3)  with
       IORING_FILE_INDEX_ALLOC  as  the  file_index  .  Upon completion, the res field of the CQE
       will return the direct slot that was allocated for the socket.

       If the direct variants are used, the application must first have registered a  file  table
       using io_uring_register_files(3) of the appropriate size. Once registered, a direct socket
       request may use any entry in that table,  as  long  as  it  is  within  the  size  of  the
       registered  table.   If  a specified entry already contains a file, the file will first be
       removed from the table and closed. It's  consistent  with  the  behavior  of  updating  an
       existing file with io_uring_register_files_update(3).

       For   a  direct  descriptor  socket  request,  the  file_index  argument  can  be  set  to
       IORING_FILE_INDEX_ALLOC, In this case a free entry in io_uring file  table  will  be  used
       automatically  and  the  file  index  will  be  returned as CQE res.  -ENFILE is otherwise
       returned if there is no free entries in the io_uring file table.

       These functions prepare an async socket(2) request. See that man page for details.

RETURN VALUE

       None

ERRORS

       The CQE res field will contain the result of the operation. See the related man  page  for
       details  on  possible  values.  Note that where synchronous system calls will return -1 on
       failure and set errno to the actual error value, io_uring never uses  errno.   Instead  it
       returns the negated errno directly in the CQE res field.

SEE ALSO

       io_uring_get_sqe(3), io_uring_submit(3), socket(2)