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<H1><A NAME="answer">
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<H4>By James T. Dennis,
<a href="mailto:linux-questions-only@ssc.com">linux-questions-only@ssc.com</a><BR>
LinuxCare,
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<H3 align="left"><img src="../../gx/dennis/qbubble.gif"
height="50" width="60" alt="(?) " border="0"
>Simple Shell and Cron Question</H3>
<p><strong>From Amir Shakib Manesh on Thu, 08 Jun 2000
</strong></p>
<!-- ::
Simple Shell and Cron Question
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
:: -->
<P><STRONG>
Dear ANswer Duy,
I want to write a shell script, in which every 15 minutes it run a simple
command, let say 'top <TT>-b</TT>'.
Would you help me?
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Well one way would be to make a cron entry like:
</BLOCKQUOTE>
<blockquote><pre>*/15 * * * * top -b
</pre></blockquote>
<BLOCKQUOTE>
... which you'd do by just issuing the command: 'crontab <TT>-e</TT>'
from your shell prompt. That should put you in an editor from
which you can type this command.
</BLOCKQUOTE>
<P><STRONG><IMG SRC="../../gx/dennis/qbub.gif" ALT="(?)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
Also is there any way to prevent from auto-log out in unix?
</STRONG></P>
<P><STRONG>
Sincerely,
</STRONG></P>
<P><STRONG>
Amir Shakib-Manesh
</STRONG></P>
<BLOCKQUOTE><IMG SRC="../../gx/dennis/bbub.gif" ALT="(!)"
HEIGHT="28" WIDTH="50" BORDER="0"
>
UNIX and Linux don't have an "auto-log out" mechanism by default.
So if you are getting logged out after some period of inactivity
then the details of how you'd bypass that depend on the mechanism
that's being used by your sysadmins. Ask them.
</BLOCKQUOTE>
<BLOCKQUOTE>
(Other than that one of the possibilities is that they are setting
a special variable in your shell, like TMOUT in bash. Read the
bash man pages and search on TMOUT to see on that works. There are
similar features in some other shells. That's a pretty common and
relatively harmless way to encourage users not to leave their
prompts unattended. Other methods involve some daemon like "idled"
which runs as 'root' and watches for inactivity, pouncing on
line hogs with 'kill' signals).
</BLOCKQUOTE>
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<H5 align="center"><a href="http://www.linuxgazette.com/copying.html"
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<BR>Published in <I>The Linux Gazette</I> Issue 55 July 2000</H5>
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