mail locking

[Richard Tobin]

Can someone tell me what locking mechanisms are used by /bin/mail and
/usr/ucb/mail under SunOS 3.x and 4.0.x (e.g. flock(), lockf(), lockfile
in /usr/spool/mail) ?

-- Richard

Richard Tobin,                       JANET: R.Tobin at uk.ac.ed             
AI Applications Institute,           ARPA:  R.Tobin%uk.ac.ed at nsfnet-relay.ac.uk
Edinburgh University.                UUCP:  ...!ukc!ed.ac.uk!R.Tobin