1io_uring_prep_sendmsg(3) liburing Manual io_uring_prep_sendmsg(3)
2
3
4
6 io_uring_prep_sendmsg - prepare a sendmsg request
7
9 #include <sys/types.h>
10 #include <sys/socket.h>
11 #include <liburing.h>
12
13 void io_uring_prep_sendmsg(struct io_uring_sqe *sqe,
14 int fd,
15 const struct msghdr *msg,
16 unsigned flags);
17
19 The io_uring_prep_sendmsg(3) function prepares a sendmsg request. The
20 submission queue entry sqe is setup to use the file descriptor fd to
21 start sending the data indicated by msg with the sendmsg(2) defined
22 flags in the flags argument.
23
24 This function prepares an async sendmsg(2) request. See that man page
25 for details.
26
27
29 None
30
32 The CQE res field will contain the result of the operation. See the re‐
33 lated man page for details on possible values. Note that where synchro‐
34 nous system calls will return -1 on failure and set errno to the actual
35 error value, io_uring never uses errno. Instead it returns the negated
36 errno directly in the CQE res field.
37
39 As with any request that passes in data in a struct, that data must re‐
40 main valid until the request has been successfully submitted. It need
41 not remain valid until completion. Once a request has been submitted,
42 the in-kernel state is stable. Very early kernels (5.4 and earlier) re‐
43 quired state to be stable until the completion occurred. Applications
44 can test for this behavior by inspecting the IORING_FEAT_SUBMIT_STABLE
45 flag passed back from io_uring_queue_init_params(3).
46
48 io_uring_get_sqe(3), io_uring_submit(3), sendmsg(2)
49
50
51
52liburing-2.2 March 12, 2022 io_uring_prep_sendmsg(3)