sosend() and mbuf

[John Baldwin]

On Tuesday 04 August 2009 12:57:25 pm Dag-Erling Smørgrav wrote:
> Ed Schouten <ed at 80386.nl> writes:
> > Maslan <maslanbsd at gmail.com> writes:
> > > However, when i checked the pid & tid of the new created thread it
> > > was not the same as the parent nor as the proc0 & thread0
> > I am not sure, but sharing another process's address space doesn't have
> > to imply it shares the same pid, right?
> 
> The man page explicitly states that if no process is specified, the new
> thread is assigned to proc0, which has a valid filedesc table, valid
> creds etc., so this shouldn't be a problem.  However, he's getting a
> different PID, which shouldn't happen.  Either the man page is wrong, or
> things were different in 7.

proc0 does not have a fully valid file descriptor table.  It has a structure, 
but fd_[cjr]dir are not initialized to point at anything.  File descriptors 
are a property of userland processes, not of kernel processes.  However, 
fd_[cjr]dir need to be valid to perform any namei() lookup even if one is 
simply going to do a vn_open() on the resulting vnode (which is more 
approprate for kernel code to do, if it is to open a file at all).

-- 
John Baldwin