Unix |
Unix v7 |
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login(1) |
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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 executes a command interpreter (usually sh(1)) according to specifications found in a password file. Argument 0 of the command interpreter is ’−sh.
Login is recognized by sh(1) and executed directly (without forking).
/etc/utmp |
accounting | |
/usr/adm/wtmp |
accounting | |
/usr/mail/* |
| |
/etc/motd |
message-of-the-day | |
/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
programming counselor.
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login(1) | ![]() |