4.4BSD/usr/share/man/cat1/lock.0

Compare this file to the similar file:
Show the results in this format: 

LOCK(1)                      BSD Reference Manual                      LOCK(1)

NNAAMMEE
     lloocckk - reserve a terminal

SSYYNNOOPPSSIISS
     lloocckk [--pp] [--tt _t_i_m_e_o_u_t]

DDEESSCCRRIIPPTTIIOONN
     LLoocckk requests a password from the user, reads it again for verification
     and then will normally not relinquish the terminal until the password is
     repeated.  There are two other conditions under which it will terminate:
     it will timeout after some interval of time and it may be killed by some-
     one with the appropriate permission.

     Options:

     --pp          A password is not requested, instead the user's current login
                 password is used.

     --tt _t_i_m_e_o_u_t  The time limit (default 15 minutes) is changed to _t_i_m_e_o_u_t
                 minutes.

HHIISSTTOORRYY
     The lloocckk command appeared in 3.0BSD.

4.4BSD                           June 6, 1993                                1