.TH login 1.SH Namelogin \- log in to a system.SH Syntax.B login[\|\fIusername\fR\|].SH Description.NXR "login command (general)".NXR "logging in".NXA "logging in" "password"The.PN logincommandis used when a user initiallysigns on, or it may be used at any time to changefrom one user to another.The latter case is the one summarized above anddescribed here.To sign on initially,see the \fIGuide to System Environment Setup\fP..PPIf.PN loginis invoked without an argument,it asks for a user name, and, ifappropriate, a password.Echoing is turned off (if possible) during the typing of the password,so it does not appear on the written record of thesession..PPAfter a successful loginaccounting files are updated,the user is informed of theexistence of mail,the message of the day is printed, andthe time of last successful login is displayed.The display of all this information can be prevented by creatingthe file.I \&.hushloginin the accounts login directory. This is useful for accounts such as.I uucp..PPIf ULTRIX security features are enabled additional things may happen.These include the display of the number of failed login attempts sincethe last successful login and forcing the setting of a new password.See the \fISecurity Guide for Users\fP and \fISecurity Guide for Administrators\fP for moreinformation..PPThe.PN logincommandinitializes the user and group IDs, the working directory,and the users audit information,then executes a command interpreter, usually .MS sh 1 ,according to specifications found in a password file.Argument 0 of the command interpreter is \*(lq\-sh\*(rq, ormore generally the name of the command interpreter witha leading dash (\*(lq\-\*(rq) prepended..PPThe .PN login command also initializes theenvironment .MS environ 7with information specifying home directory,command interpreter, terminaltype (if available) and user name..PPWhen.PN loginis used in conjunction with.MS getty 8it is the responsibility of the getty program to initialize theterminal attributes.  Specifically if a terminal is setup to use 8-bit characters the .PN gettyprogram should use a .MS gettytab 5 entry which specifies 8-bit characters.  If a terminal is setup in8-bit mode but fails to specify an 8-bit gettytab entry, thencharacters output by both .PN loginand.PN gettymay appear as multinational characters.  .PPIf the file .PN /etc/nologinexists,.PN loginprints its contents on the user's terminal and exits. This isused by .MS shutdown 8to stop users logging in when the system is about to go down..PPThe.PN login command is recognized by .MS sh 1 and .MS csh 1and executed directly (without forking)..PPIf a root login is attempted and an invalid commandinterpreter is specified, the .PN shinterpreter is used..SH Options.IP \fB\-r\fR 20Used by the remote login server, .MS rlogind 8c ,to force.PN loginto enter into an initial connection protocol..IP "\fB\-P \fI<programname>\fR" 20Causes.PN loginto set it's standard inputand output to be connected to the prompting program \fI<programname>\fR..IP "\fB\-C \fIstring\fR" 20Allows the system to specify a command to be run using theuser's shell.  This option causes a user shell.B \-c\fIstring\fR to be .PN exec 'ed..IP \fB\-e\fR 20Forces.PN loginto use an extended protocol when communicating with a prompterprogram (see \-P)..SH RestrictionsTo provide flow control, CTRL/S andCTRL/Q are ignored and aretherefore invalid characters in a login name.  .SH Diagnostics.NXR "login command (general)" "diagnostics".PP.B "Login incorrect".brIf the username and password are not a valid combination..PP.B "Too many users logged on already. Try again later.".brThe system has the maximum licensed number of users logged on already..PP.B "License not valid for this version of ULTRIX.".brThe PAK that has been registered is for an earlier version of ULTRIX..PP.B "No valid license found for ULTRIX.".brThere is either no ULTRIX PAK registered or the PAK that hasbeen found is not valid, possibly because it has terminated..PP.B "Requires secure terminal".brAn attempt was made to login as UID 0 on a line that is not markedas \fIsecure\fP in.PN /etc/ttys ..PP.B "No shell".brThe login shell specified for the account cannot be executed. Consultthe system administrator..PP.B "No directory! Logging in with home=/".brThe HOME directory for the account is inaccessible. This can happenif the directory resides on an NFS file system served by a host thatis not currently available..PP.B "You have too many processes running".brCompletion of login would exceed the maximum number of running processesallowed for the user..PP.B "You have mail".brYou have a non-empty mail spool file..PPIf ULTRIX security features are enabled the following messages arealso possible from login:.PP.PP.B "Your password has expired".brThe password for your account has not been changed recently enough.Consult your system administrator..PP.B "Your password has expired, please change it".brYour password has expired recently. You have to change itbefore you can proceed any further..PP.B "Your password will expire very soon".brYour password will expire in less than 24 hours..PP.B "Your password will expire in %d days".brThe ``%d'' is replaced with the number of days until yourpassword expires. You should consider changing your password now..PP.B "This account is disabled".brConsult your system administrator..PP.B "Kerberos initialization failure".brConsult your system administrator..SH Files.PD 0.TP 20.PN /etc/utmpaccounting.TP.PN /usr/adm/wtmpaccounting.TP.PN /usr/spool/mail/*mail.TP.PN /etc/motdmessage-of-the-day.TP.PN /etc/auth.[pag,dir]authorization data base.TP.PN /etc/passwdpassword file.TP.PN /etc/nologinstops logins.TP.PN /etc/svc.confsets I&A security level.TP.PN \&.hushloginmakes login quieter.TP.PN /etc/securettylists ttys that root may log in on.SH See Alsomail(1), passwd(1), yppasswd(1yp), passwd(5yp), environ(7),getty(8), init(8), rlogind(8c), shutdown(8).br\fIGuide to System Environment Setup\fP.br\fISecurity Guide for Users\fP.br\fISecurity Guide for Administrators\fP