more uses for mode 000 (will be: cat -v considered harmful)

[Guy Harris]

>A permanent fix would be to have a dynamically-sized u_area, or
>whatever it's called now. The arg list could then be stored in it, no
>matter how large it gets (within address space limitations).

It's generally still called the U area; however, it generally does *not*
store the arg list (System V systems may store the first 80 or so
characters of it as a string with blanks between them, for the benefit
of "ps", but that's different).  Perhaps it could be made to do so;
however, at least one of the systems that supports huge argument lists,
namely SunOS 4.x (1MB of args), manages to do so without storing arg
lists in a dynamically-sized U area.  Dunno about other systems that do
(I believe S5R4 and some of the later Research UNIXes do), but I suspect
they don't do so, either.