Question about IORING_FEAT_LINKED_FILE

[realwakka]

In man page, there is an feature IORING_FEAT_LINKED_FILE for io_uring_setup
I understand that it enables SQEs could have dependencies like open - read - close.
Also, in this Issue I know it can be achived with io_uring_register_files_sparse()
It seems that no code in kernel working with IORING_FEAT_LINKED_FILE. and I can't find an example for this.
Is it deprecated option? or did I missed something?

[isilence]

Note that the flag, just as all other `IORING_FEAT*" flags, is set by the kernel to inform the user space about the behaviour, not the other way around. In other words, you can check it if you need the behaviour, but the user space doesn't control it.

struct io_uring_params params;
io_uring_queue_init_params(..., &params);

if (params.features & IORING_FEAT_LINKED_FILE) {
    // do linked open + read
} else {
    // don't use links
}

[realwakka]

Thanks for detailed answer. I understood that it's not a option user provides but it shows how to work in kernel.