Copyright (C) 2021 Stefan Roesch <[email protected]>

SPDX-License-Identifier: LGPL-2.0-or-later

io_uring_cqe_get_data - get user data for completion event

 #include <liburing.h> 

 "void *io_uring_cqe_get_data(struct io_uring_cqe *" cqe ");"  "  "__u64 io_uring_cqe_get_data64(struct io_uring_cqe *" cqe ");" 

The io_uring_cqe_get_data (3) function returns the user_data with the completion queue entry cqe as a data pointer. The io_uring_cqe_get_data64 (3) function returns the user_data with the completion queue entry cqe as a 64-bit data value. After the caller has received a completion queue entry (CQE) with io_uring_wait_cqe (3), the application can call io_uring_cqe_get_data (3) or io_uring_cqe_get_data64 (3) function to retrieve the user_data value. This requires that user_data has been set earlier with the function io_uring_sqe_set_data (3) or io_uring_sqe_set_data64 (3).

If the user_data value has been set before submitting the request, it will be returned. Otherwise the functions returns NULL. io_uring_get_sqe (3), io_uring_sqe_set_data (3), io_uring_sqe_submit (3)