[HEADSUP] Disallowing read() of a directory fd

[grarpamp]

> Another use of "cat ." is to see names of transient files a tool
> creates, & normaly deletes

People in fora have been seen doing this, often
after discovering read works after figuring what
command arguments blew up their screen.

> so one can find same
> name junk elsewhere, & search for tool causing junk,

Many might not like managing
 ktrace -ditnp 1
then again unfortunately there may still not be anyone offering
useful kernel module ports that might log all pathname add/use/del,
save its contents somewhere, log all keystrokes in shells, etc.

> & ensure other data files avoid using names that would be zapped.

mkstemp(3)