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diff --git a/sag-0.6.1-www/Invisible/sag-0.6/node82.html b/sag-0.6.1-www/Invisible/sag-0.6/node82.html new file mode 100644 index 0000000..54ab87b --- /dev/null +++ b/sag-0.6.1-www/Invisible/sag-0.6/node82.html @@ -0,0 +1,65 @@ +<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN"> +<!--Converted with LaTeX2HTML 96.1-h (September 30, 1996) by Nikos Drakos (nikos@cbl.leeds.ac.uk), CBLU, University of Leeds --> +<HTML> +<HEAD> +<TITLE>What login does</TITLE> +<META NAME="description" CONTENT="What login does"> +<META NAME="keywords" CONTENT="sag"> +<META NAME="resource-type" CONTENT="document"> +<META NAME="distribution" CONTENT="global"> +<LINK REL=STYLESHEET HREF="sag.css"> +</HEAD> +<BODY LANG="EN" > + <A NAME="tex2html1345" HREF="node83.html"><IMG WIDTH=37 HEIGHT=24 ALIGN=BOTTOM ALT="next" SRC="./next_motif.gif"></A> <A NAME="tex2html1343" HREF="node79.html"><IMG WIDTH=26 HEIGHT=24 ALIGN=BOTTOM ALT="up" SRC="./up_motif.gif"></A> <A NAME="tex2html1337" HREF="node81.html"><IMG WIDTH=63 HEIGHT=24 ALIGN=BOTTOM ALT="previous" SRC="./previous_motif.gif"></A> <A NAME="tex2html1347" HREF="node1.html"><IMG WIDTH=65 HEIGHT=24 ALIGN=BOTTOM ALT="contents" SRC="./contents_motif.gif"></A> <A NAME="tex2html1348" HREF="node114.html"><IMG WIDTH=43 HEIGHT=24 ALIGN=BOTTOM ALT="index" SRC="./index_motif.gif"></A> <BR> +<B> Next:</B> <A NAME="tex2html1346" HREF="node83.html">X and xdm</A> +<B>Up:</B> <A NAME="tex2html1344" HREF="node79.html">Logging In And Out</A> +<B> Previous:</B> <A NAME="tex2html1338" HREF="node81.html">Logins via the network</A> +<BR> <P> +<A NAME="2646"> </A><H1><A NAME="SECTION00930000000000000000">What <tt>login</tt> does</A></H1> +<P> + The <tt>login</tt><A NAME="2648"> </A> program takes care of authenticating the user + (making sure that the username and password match), and of + setting up an initial environment for the user by setting + permissions for the serial line and starting the shell. +<P> + Part of the initial setup is outputting the contents of the + file <tt>/etc/motd</tt><A NAME="2650"> </A> (short for message of the day) and checking + for electronic mail. These can be disabled by creating a file + called <tt>.hushlogin</tt><A NAME="2652"> </A> in the user's home directory. +<P> + If the file <tt>/etc/nologin</tt><A NAME="2654"> </A> exists, logins are + disabled. That file is typically created by <tt>shutdown</tt><A NAME="2656"> </A> + and relatives. <tt>login</tt><A NAME="2658"> </A> checks for this file, and will + refuse to accept a login if it exists. If it does exist, + <tt>login</tt><A NAME="2660"> </A> outputs its contents to the terminal before it quits. +<P> + <tt>login</tt><A NAME="2662"> </A> logs all failed login attempts in a system log file + (via <tt>syslog</tt><A NAME="2664"> </A>). It also logs <em>all</em> logins by <tt>root</tt>. + Both of these can be useful when tracking down intruders. +<P> + Currently logged in people are listed in <tt>/var/run/utmp</tt><A NAME="2666"> </A>. + This file is valid only until the system is next rebooted or shut + down; it is cleared when the system is booted. It lists each + user and the terminal (or network connection) he is using, along + with some other useful information. The <tt>who</tt><A NAME="2668"> </A>, <tt>w</tt><A NAME="2670"> </A>, and + other similar commands look in <tt>utmp</tt><A NAME="2672"> </A> to see who are logged in. +<P> + All successful logins are recorded into <tt>/var/log/wtmp</tt><A NAME="2674"> </A>. + This file will grow without limit, so it must be cleaned + regularly, for example by having a weekly <tt>cron</tt><A NAME="2676"> </A> job + to clear it.<A NAME="tex2html40" HREF="footnode.html#2559"><IMG ALIGN=BOTTOM ALT="gif" SRC="./foot_motif.gif"></A> The <tt>last</tt><A NAME="2678"> </A> command browses <tt>wtmp</tt><A NAME="2680"> </A>. +<P> + Both <tt>utmp</tt><A NAME="2682"> </A> and <tt>wtmp</tt><A NAME="2684"> </A> are in a binary format (see the + <em>utmp</em><A NAME="2686"> </A> manual page); it is unfortunately not convenient + to examine them without special programs. +<P> +<HR><A NAME="tex2html1345" HREF="node83.html"><IMG WIDTH=37 HEIGHT=24 ALIGN=BOTTOM ALT="next" SRC="./next_motif.gif"></A> <A NAME="tex2html1343" HREF="node79.html"><IMG WIDTH=26 HEIGHT=24 ALIGN=BOTTOM ALT="up" SRC="./up_motif.gif"></A> <A NAME="tex2html1337" HREF="node81.html"><IMG WIDTH=63 HEIGHT=24 ALIGN=BOTTOM ALT="previous" SRC="./previous_motif.gif"></A> <A NAME="tex2html1347" HREF="node1.html"><IMG WIDTH=65 HEIGHT=24 ALIGN=BOTTOM ALT="contents" SRC="./contents_motif.gif"></A> <A NAME="tex2html1348" HREF="node114.html"><IMG WIDTH=43 HEIGHT=24 ALIGN=BOTTOM ALT="index" SRC="./index_motif.gif"></A> <BR> +<B> Next:</B> <A NAME="tex2html1346" HREF="node83.html">X and xdm</A> +<B>Up:</B> <A NAME="tex2html1344" HREF="node79.html">Logging In And Out</A> +<B> Previous:</B> <A NAME="tex2html1338" HREF="node81.html">Logins via the network</A> +<P><ADDRESS> +<I>Lars Wirzenius <BR> +Sat Nov 15 02:32:11 EET 1997</I> +</ADDRESS> +</BODY> +</HTML> |