passwd file maint utilities - shadowing

[Dr. Scump]

Several questions related to the shadow passwd file (/etc/shadow):

1) which versions of UNIX use it by default?  With which version did
   shadowing begin - SVR2?  SVR3?  SVR3 Rel 3.2 ?  other?  Is it
   the same for AT&T and other System V vendors?

2) with those versions which use shadowing by default -- can it be
   turned "off" just by removing /etc/shadow and restoring passwords
   to /etc/passwd?

3) do shadowing UNIX versions all use the same utilities?  The only
   ones that I am familiar with are AT&T's (adduser, deluser, passmgmt).
   Do the other vendors use the same utility names and parameter usage?

4) also, is there a way to *set* a passwd from a script?  /bin/passwd
   seems to insist on interactive use.  I can remove a passwd (via
   /bin/passwd -d username) but not set one, as far as I can see.
   I checked everywhere in TFM that I can think of.

Thanks in advance.   Followups to comp.unix.questions.

--
Alan S. Denney # Informix # aland at informix.com # {pyramid|uunet}!infmx!aland
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