mutex locking on file descriptors?

[Wall, Stephen]

I've been told by a co-worker that a freebsd developer once told him that mutex locking on socket descriptors was not necessary to avoid issues with multiple threads reading and writing.  I would like to confirm this is true of file descriptors as well, and in particular of device driver file descriptors, before I abandon them in my code.  The driver in question is a simple `usb_fifo_methods` type driver.


Thanks.


- Steve Wall