Re: /proc/<pid>/{cwd, root} links to <defunct> for cygrunsrv, daemons, and shells

[Corinna Vinschen <corinna-cygwin@cygwin.com>]

On Apr  9 10:38, Brian Inglis wrote:
> On 2024-04-09 07:08, Corinna Vinschen wrote:
> > That's typically a permission problem.  On Linux you get something like
> > 
> >    ls: cannot read symbolic link '/proc/1/cwd': Permission denied
> 
> Thanks Corinna,
> 
> That now makes sense, as Cygwin ps -a and btop showed the processes,
> although procps and top did not, and other info is visible, I never thought
> about permissions as there were links, but I see from elevated admin sh:
> [...]
> so I think perms on these should be 440 or 550 not 444 or 555, but that may
> involve a lot of work to decide that for each entry?

Not really.  Have a look into fhandler/proc.cc, fhandler/process.cc,
etc.  We can add a permisions member to struct virt_tab_t and add
this as static info to every member in the list.  Doesn't sound overly
complicated to me (*nudge, nudge*).

Changing <defunct> to a "Permission denied" when trying to open a
virtual symlink may be a bit more involved, but maybe not very much.


Corinna