1io_uring_prep_socket(3) liburing Manual io_uring_prep_socket(3)
2
6 io_uring_prep_socket - prepare a socket creation request
7
9 #include <sys/socket.h>
10 #include <liburing.h>
11 void io_uring_prep_socket(struct io_uring_sqe *sqe,
13 int domain,
14 int type,
15 int protocol,
16 unsigned int flags);
17 void io_uring_prep_socket_direct(struct io_uring_sqe *sqe,
19 int domain,
20 int type,
21 int protocol,
22 unsigned int file_index,
23 unsigned int flags);
24 void io_uring_prep_socket_direct_alloc(struct io_uring_sqe *sqe,
26 int domain,
27 int type,
28 int protocol,
29 unsigned int flags);
30
32 The io_uring_prep_socket(3) function prepares a socket creation re‐
33 quest. The submission queue entry sqe is setup to use the communication
34 domain defined by domain and use the communication type defined by type
35 and the protocol set by protocol. The flags argument are currently un‐
36 used.
37 The io_uring_prep_socket_direct(3) helper works just like io_ur‐
39 ing_prep_socket(3), except it maps the socket to a direct descriptor
40 rather than return a normal file descriptor. The file_index argument
41 should be set to the slot that should be used for this socket.
42 The io_uring_prep_socket_direct_alloc(3) helper works just like io_ur‐
44 ing_prep_socket_alloc(3), except it allocates a new direct descriptor
45 rather than pass a free slot in. It is equivalent to using io_ur‐
46 ing_prep_socket_direct(3) with IORING_FILE_INDEX_ALLOC as the file_in‐
47 dex . Upon completion, the res field of the CQE will return the direct
48 slot that was allocated for the socket.
49 If the direct variants are used, the application must first have regis‐
51 tered a file table using io_uring_register_files(3) of the appropriate
52 size. Once registered, a direct socket request may use any entry in
53 that table, as long as it is within the size of the registered table.
54 If a specified entry already contains a file, the file will first be
55 removed from the table and closed. It's consistent with the behavior of
56 updating an existing file with io_uring_register_files_update(3).
57 For a direct descriptor socket request, the file_index argument can be
59 set to IORING_FILE_INDEX_ALLOC, In this case a free entry in io_uring
60 file table will be used automatically and the file index will be re‐
61 turned as CQE res. -ENFILE is otherwise returned if there is no free
62 entries in the io_uring file table.
63 These functions prepare an async socket(2) request. See that man page
65 for details.
66
69 None
70
72 The CQE res field will contain the result of the operation. See the re‐
73 lated man page for details on possible values. Note that where synchro‐
74 nous system calls will return -1 on failure and set errno to the actual
75 error value, io_uring never uses errno. Instead it returns the negated
76 errno directly in the CQE res field.
77
79 io_uring_get_sqe(3), io_uring_submit(3), socket(2)
80liburing-2.2 May 27, 2022 io_uring_prep_socket(3)