Function send_zc [src]

Queues (but does not submit) an SQE to perform an async zerocopy send(2). This operation will most likely produce two CQEs. The flags field of the first cqe may likely contain IORING_CQE_F_MORE, which means that there will be a second cqe with the user_data field set to the same value. The user must not modify the data buffer until the notification is posted. The first cqe follows the usual rules and so its res field will contain the number of bytes sent or a negative error code. The notification's res field will be set to zero and the flags field will contain IORING_CQE_F_NOTIF. The two step model is needed because the kernel may hold on to buffers for a long time, e.g. waiting for a TCP ACK. Notifications responsible for controlling the lifetime of the buffers. Even errored requests may generate a notification. Available since 6.0

Prototype

 pub fn send_zc( self: *IoUring, user_data: u64, fd: posix.fd_t, buffer: []const u8, send_flags: u32, zc_flags: u16, ) !*linux.io_uring_sqe

Parameters

self: *IoUringuser_data: u64fd: posix.fd_tbuffer: []const u8send_flags: u32zc_flags: u16

Source

  pub fn send_zc(
    self: *IoUring,
    user_data: u64,
    fd: posix.fd_t,
    buffer: []const u8,
    send_flags: u32,
    zc_flags: u16,
) !*linux.io_uring_sqe {
    const sqe = try self.get_sqe();
    sqe.prep_send_zc(fd, buffer, send_flags, zc_flags);
    sqe.user_data = user_data;
    return sqe;
}  