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Miller" , Jakub Kicinski , Network Development , linux-wireless@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org On Tue, 8 Jun 2021 at 06:02, Sergey Ryazanov wrote: > > It is quite common for a userpace program to fetch the buffered amount > of data in the rx queue to avoid the read block. Implement the TIOCINQ > ioctl to make the migration to the WWAN port usage smooth. > > Despite the fact that the read call will return no more data than the > size of a first skb in the queue, TIOCINQ returns the entire amount of > buffered data (sum of all queued skbs). This is done to prevent the > breaking of programs that optimize reading, avoiding it if the buffered > amount of data is too small. > > Signed-off-by: Sergey Ryazanov Reviewed-by: Loic Poulain