Anonymous AWK fan via 9fans <9fans@9fans.net> once said: > The comments on the #define lines and a commented out section of > stat(2) say (DM|QT)MOUNT indicates a mounted channel, what is this? > > Also, why does exportfs fork and the kernel not send write on closed > pipe notes for mounted channels?
When you call mount(2), the mnt(3) driver attempts to negotiate a conversation with the 9p server on the other end of the supplied file descriptor. If the negotiation is successful, the kernel sets a flag on the underlying channel to restrict the set of operations available to user space until the file descriptor is closed. If this wasn't done, any reads, writes, or seeks would interfere with the mount driver's ongoing 9p conversation. Cheers, Anthony ------------------------------------------ 9fans: 9fans Permalink: https://9fans.topicbox.com/groups/9fans/T07cb7686febe72c8-M1734aaea903ed27f61612f56 Delivery options: https://9fans.topicbox.com/groups/9fans/subscription
