LOGIN(1) General Commands Manual LOGIN(1)
login - sign on
login [ username ]
The login command is used when a user initially signs on, or it may be
used at any time to change from one user to another. The latter case
is the one summarized above and described here. See `How to Get
Started' for how to dial up initially.
If login is invoked without an argument, it asks for a user name, and,
if appropriate, a password. Echoing is turned off (if possible) during
the typing of the password, so it will not appear on the written record
of the session.
After a successful login, accounting files are updated and the user is
informed of the existence of .mail and message-of-the-day files. Login
initializes the user and group IDs and the working directory, then exe-
cutes a command interpreter (usually sh(1)) according to specifications
found in a password file. Argument 0 of the command interpreter is
Login is recognized by sh(1) and executed directly (without forking).
/etc/passwd password file
init(8), newgrp(1), getty(8), mail(1), passwd(1), passwd(5)
`Login incorrect,' if the name or the password is bad.
`No Shell', `cannot open password file', `no directory': consult a pro-