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<!DOCTYPE HTML PUBLIC "-//Norman Walsh//DTD DocBook HTML 1.0//EN">
<HTML
><HEAD
><TITLE
>The /var filesystem</TITLE
><META
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><TR
><TH
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ALIGN="center"
>The Linux System Administrators' Guide</TH
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><TR
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ALIGN="left"
VALIGN="bottom"
><A
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>Prev</A
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></TABLE
><HR
ALIGN="LEFT"
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><DIV
CLASS="SECT1"
><H1
CLASS="SECT1"
><A
NAME="AEN531"
>The <TT
CLASS="FILENAME"
>/var</TT
> filesystem</A
></H1
><P
>The <TT
CLASS="FILENAME"
>/var</TT
> contains data that is changed when the system is
running normally. It is specific for each system, i.e., not
shared over the network with other computers.
<DIV
CLASS="GLOSSLIST"
><DL
><DT
><B
><TT
CLASS="FILENAME"
>/var/catman</TT
></B
></DT
><DD
><P
>A cache for man pages that are formatted
on demand. The source for manual pages is usually
stored in <TT
CLASS="FILENAME"
>/usr/man/man*</TT
>; some
manual pages might come with a pre-formatted version,
which is stored in <TT
CLASS="FILENAME"
>/usr/man/cat*</TT
>.
Other manual pages need to be formatted when they are
first viewed; the formatted version is then stored
in <TT
CLASS="FILENAME"
>/var/man</TT
> so that the next
person to view the same page won't have to wait for
it to be formatted. (<TT
CLASS="FILENAME"
>/var/catman</TT
>
is often cleaned in the same way temporary directories
are cleaned.)</P
></DD
><DT
><B
><TT
CLASS="FILENAME"
>/var/lib</TT
></B
></DT
><DD
><P
>Files that change while the system is
running normally.</P
></DD
><DT
><B
><TT
CLASS="FILENAME"
>/var/local</TT
></B
></DT
><DD
><P
>Variable data for programs that are
installed in <TT
CLASS="FILENAME"
>/usr/local</TT
> (i.e.,
programs that have been installed by the system
administrator). Note that even locally installed
programs should use the other <TT
CLASS="FILENAME"
>/var</TT
>
directories if they are appropriate, e.g.,
<TT
CLASS="FILENAME"
>/var/lock</TT
>.</P
></DD
><DT
><B
><TT
CLASS="FILENAME"
>/var/lock</TT
></B
></DT
><DD
><P
>Lock files. Many programs
follow a convention to create a lock file in
<TT
CLASS="FILENAME"
>/var/lock</TT
> to indicate that they
are using a particular device or file. Other programs
will notice the lock file and won't attempt to use the
device or file.</P
></DD
><DT
><B
><TT
CLASS="FILENAME"
>/var/log</TT
></B
></DT
><DD
><P
>Log files from various
programs, especially <B
CLASS="COMMAND"
>login</B
>
(<TT
CLASS="FILENAME"
>/var/log/wtmp</TT
>, which logs all logins
and logouts into the system) and <B
CLASS="COMMAND"
>syslog</B
>
(<TT
CLASS="FILENAME"
>/var/log/messages</TT
>, where all
kernel and system program message are usually stored).
Files in <TT
CLASS="FILENAME"
>/var/log</TT
> can often grow
indefinitely, and may require cleaning at regular
intervals.</P
></DD
><DT
><B
><TT
CLASS="FILENAME"
>/var/run</TT
></B
></DT
><DD
><P
>Files that contain information about the
system that is valid until the system is next booted.
For example, <TT
CLASS="FILENAME"
>/var/run/utmp</TT
>
contains information about people currently logged
in.</P
></DD
><DT
><B
><TT
CLASS="FILENAME"
>/var/spool</TT
></B
></DT
><DD
><P
>Directories for mail,
news, printer queues, and other queued work.
Each different spool has its own subdirectory
below <TT
CLASS="FILENAME"
>/var/spool</TT
>,
e.g., the mailboxes of the users are in
<TT
CLASS="FILENAME"
>/var/spool/mail</TT
>.</P
></DD
><DT
><B
><TT
CLASS="FILENAME"
>/var/tmp</TT
></B
></DT
><DD
><P
>Temporary files that are large
or that need to exist for a longer time than
what is allowed for <TT
CLASS="FILENAME"
>/tmp</TT
>.
(Although the system administrator might not allow
very old files in <TT
CLASS="FILENAME"
>/var/tmp</TT
>
either.)</P
></DD
></DL
></DIV
></P
></DIV
><DIV
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><HR
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><TD
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VALIGN="top"
><A
HREF="x472.html"
>Prev</A
></TD
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ALIGN="center"
VALIGN="top"
><A
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>Home</A
></TD
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><A
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>Next</A
></TD
></TR
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
>The <TT
CLASS="FILENAME"
>/usr</TT
> filesystem</TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="c212.html"
>Up</A
></TD
><TD
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>The <TT
CLASS="FILENAME"
>/proc</TT
> filesystem</TD
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>
|
