source: chapter06/util-linux.xml@ 9373e03

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<sect1 id="ch-system-util-linux" xreflabel="Util-linux" role="wrap">
<title>Util-linux-&util-linux-version;</title>
<?dbhtml filename="util-linux.html"?>

<indexterm zone="ch-system-util-linux"><primary sortas="a-Util-linux">Util-linux</primary></indexterm>

<sect2 role="package"><title/>
<para>The Util-linux package contains miscellaneous utility programs. Among
them are utilities for handling file systems, consoles, partitions, and
messages.</para>

<segmentedlist>
<segtitle>&buildtime;</segtitle>
<segtitle>&diskspace;</segtitle>
<seglistitem><seg>0.2 SBU</seg><seg>16 MB</seg></seglistitem>
</segmentedlist>

<segmentedlist>
<segtitle>Util-linux installation depends on</segtitle>
<seglistitem><seg>Bash, Binutils, Coreutils,
Diffutils, GCC, Gettext, Glibc, Grep, Make, Ncurses, Sed, Zlib</seg></seglistitem>
</segmentedlist>
</sect2>

<sect2 role="installation">
<title>FHS compliance notes</title>

<para>The FHS recommends that we use <filename class="directory">/var/lib/hwclock</filename>,
instead of the usual <filename class="directory">/etc</filename>, as the location for the
<filename>adjtime</filename> file. To make the <command>hwclock</command>
program FHS-compliant, run the following:</para>

<screen><userinput>sed -i 's@etc/adjtime@var/lib/hwclock/adjtime@g' hwclock/hwclock.c
mkdir -p /var/lib/hwclock</userinput></screen>

</sect2>

<sect2 role="installation">
<title>Installation of Util-linux</title>

<para>Util-Linux has a coding problem that causes mis-compilation of the sfdisk
program.  This patch fixes the problem:</para>

<para>Prepare Util-linux for compilation:</para>

<screen><userinput>./configure</userinput></screen>

<para>Compile the package:</para>

<screen><userinput>make HAVE_KILL=yes HAVE_SLN=yes</userinput></screen>

<para>The meaning of the make parameters:</para>

<variablelist>
<varlistentry>
<term><parameter>HAVE_KILL=yes</parameter></term>
<listitem><para>This prevents the
<command>kill</command> program (already installed by Procps) from being
built and installed again.</para></listitem>
</varlistentry>

<varlistentry>
<term><parameter>HAVE_SLN=yes</parameter></term>
<listitem><para>This prevents the
<command>sln</command> program (a statically linked
<command>ln</command> already installed by Glibc) from being built and
installed again.</para></listitem>
</varlistentry>
</variablelist>

<para>Now install the package:</para>

<screen><userinput>make HAVE_KILL=yes HAVE_SLN=yes install</userinput></screen>

</sect2>


<sect2 id="contents-utillinux" role="content"><title>Contents of Util-linux</title>

<segmentedlist>
<segtitle>Installed programs</segtitle>
<seglistitem><seg>agetty, arch, blockdev, cal, cfdisk, chkdupexe, col, colcrt, 
colrm, column, ctrlaltdel, cytune, ddate, dmesg, elvtune, fdformat, fdisk, 
fsck.cramfs, fsck.minix, getopt, hexdump, hwclock, ipcrm, ipcs, isosize, line, 
logger, look, losetup, mcookie, mkfs, mkfs.bfs, mkfs.cramfs, mkfs.minix, mkswap, 
more, mount, namei, pg, pivot_root, ramsize (link to rdev), raw, rdev, readprofile, 
rename, renice, rev, rootflags (link to rdev), script, setfdprm, setsid, setterm, 
sfdisk, swapoff (link to swapon), swapon, tunelp, ul, umount, vidmode (link to rdev), 
whereis and write</seg></seglistitem>
</segmentedlist>

<variablelist><title>Short descriptions</title>

<varlistentry id="agetty">
<term><command>agetty</command></term>
<listitem>
<indexterm zone="ch-system-util-linux agetty"><primary sortas="b-agetty">agetty</primary></indexterm>
<para>opens a tty port, prompts for a login name,
and then invokes the <command>login</command> program.</para>
</listitem>
</varlistentry>

<varlistentry id="arch">
<term><command>arch</command></term>
<listitem>
<indexterm zone="ch-system-util-linux arch"><primary sortas="b-arch">arch</primary></indexterm>
<para>reports the machine's architecture.</para>
</listitem>
</varlistentry>

<varlistentry id="blockdev">
<term><command>blockdev</command></term>
<listitem>
<indexterm zone="ch-system-util-linux blockdev"><primary sortas="b-blockdev">blockdev</primary></indexterm>
<para>allows you to call block device ioctls from the command line.</para>
</listitem>
</varlistentry>

<varlistentry id="cal">
<term><command>cal</command></term>
<listitem>
<indexterm zone="ch-system-util-linux cal"><primary sortas="b-cal">cal</primary></indexterm>
<para>displays a simple calendar.</para>
</listitem>
</varlistentry>

<varlistentry id="cfdisk">
<term><command>cfdisk</command></term>
<listitem>
<indexterm zone="ch-system-util-linux cfdisk"><primary sortas="b-cfdisk">cfdisk</primary></indexterm>
<para>is used to manipulate the partition table of the given device.</para>
</listitem>
</varlistentry>

<varlistentry id="chkdupexe">
<term><command>chkdupexe</command></term>
<listitem>
<indexterm zone="ch-system-util-linux chkdupexe"><primary sortas="b-chkdupexe">chkdupexe</primary></indexterm>
<para>finds duplicate executables.</para>
</listitem>
</varlistentry>

<varlistentry id="col">
<term><command>col</command></term>
<listitem>
<indexterm zone="ch-system-util-linux col"><primary sortas="b-col">col</primary></indexterm>
<para>filters out reverse line feeds.</para>
</listitem>
</varlistentry>

<varlistentry id="colcrt">
<term><command>colcrt</command></term>
<listitem>
<indexterm zone="ch-system-util-linux colcrt"><primary sortas="b-colcrt">colcrt</primary></indexterm>
<para>is used to filter nroff output for terminals
that lack some capabilities such as overstriking and half-lines.</para>
</listitem>
</varlistentry>

<varlistentry id="colrm">
<term><command>colrm</command></term>
<listitem>
<indexterm zone="ch-system-util-linux colrm"><primary sortas="b-colrm">colrm</primary></indexterm>
<para>filters out the given columns.</para>
</listitem>
</varlistentry>

<varlistentry id="column">
<term><command>column</command></term>
<listitem>
<indexterm zone="ch-system-util-linux column"><primary sortas="b-column">column</primary></indexterm>
<para>formats a given file into multiple columns.</para>
</listitem>
</varlistentry>

<varlistentry id="ctrlaltdel">
<term><command>ctrlaltdel</command></term>
<listitem>
<indexterm zone="ch-system-util-linux ctrlaltdel"><primary sortas="b-ctrlaltdel">ctrlaltdel</primary></indexterm>
<para>sets the function of the Ctrl+Alt+Del key combination to a hard or a 
soft reset.</para>
</listitem>
</varlistentry>

<varlistentry id="cytune">
<term><command>cytune</command></term>
<listitem>
<indexterm zone="ch-system-util-linux cytune"><primary sortas="b-cytune">cytune</primary></indexterm>
<para>was used to tune the parameters of the
serial line drivers for Cyclades cards.</para>
</listitem>
</varlistentry>

<varlistentry id="ddate">
<term><command>ddate</command></term>
<listitem>
<indexterm zone="ch-system-util-linux ddate"><primary sortas="b-ddate">ddate</primary></indexterm>
<para>gives the Discordian date, or converts the
given Gregorian date to a Discordian one.</para>
</listitem>
</varlistentry>

<varlistentry id="dmesg">
<term><command>dmesg</command></term>
<listitem>
<indexterm zone="ch-system-util-linux dmesg"><primary sortas="b-dmesg">dmesg</primary></indexterm>
<para>dumps the kernel boot messages.</para>
</listitem>
</varlistentry>

<varlistentry id="elvtune">
<term><command>elvtune</command></term>
<listitem>
<indexterm zone="ch-system-util-linux elvtune"><primary sortas="b-elvtune">elvtune</primary></indexterm>
<para>can be used to tune the performance
and interactivity of a block device.</para>
</listitem>
</varlistentry>

<varlistentry id="fdformat">
<term><command>fdformat</command></term>
<listitem>
<indexterm zone="ch-system-util-linux fdformat"><primary sortas="b-fdformat">fdformat</primary></indexterm>
<para>low-level formats a floppy disk.</para>
</listitem>
</varlistentry>

<varlistentry id="fdisk">
<term><command>fdisk</command></term>
<listitem>
<indexterm zone="ch-system-util-linux fdisk"><primary sortas="b-fdisk">fdisk</primary></indexterm>
<para>could be used to manipulate the partition table of the given device.</para>
</listitem>
</varlistentry>

<varlistentry id="fsck.cramfs">
<term><command>fsck.cramfs</command></term>
<listitem>
<indexterm zone="ch-system-util-linux fsck.cramfs"><primary sortas="b-fsck.cramfs">fsck.cramfs</primary></indexterm>
<para>performs a consistency check on the
Cramfs file system on the given device.</para>
</listitem>
</varlistentry>

<varlistentry id="fsck.minix">
<term><command>fsck.minix</command></term>
<listitem>
<indexterm zone="ch-system-util-linux fsck.minix"><primary sortas="b-fsck.minix">fsck.minix</primary></indexterm>
<para>performs a consistency check on the
Minix file system on the given device.</para>
</listitem>
</varlistentry>

<varlistentry id="getopt">
<term><command>getopt</command></term>
<listitem>
<indexterm zone="ch-system-util-linux getopt"><primary sortas="b-getopt">getopt</primary></indexterm>
<para>parses options in the given command line.</para>
</listitem>
</varlistentry>

<varlistentry id="hexdump">
<term><command>hexdump</command></term>
<listitem>
<indexterm zone="ch-system-util-linux hexdump"><primary sortas="b-hexdump">hexdump</primary></indexterm>
<para>dumps the given file in hexadecimal, or in another given format.</para>
</listitem>
</varlistentry>

<varlistentry id="hwclock">
<term><command>hwclock</command></term>
<listitem>
<indexterm zone="ch-system-util-linux hwclock"><primary sortas="b-hwclock">hwclock</primary></indexterm>
<para>is used to read or set the system's hardware clock, also called the RTC 
(Real-Time Clock) or BIOS (Basic Input-Output System) clock.</para>
</listitem>
</varlistentry>

<varlistentry id="ipcrm">
<term><command>ipcrm</command></term>
<listitem>
<indexterm zone="ch-system-util-linux ipcrm"><primary sortas="b-ipcrm">ipcrm</primary></indexterm>
<para>removes the given IPC resource.</para>
</listitem>
</varlistentry>

<varlistentry id="ipcs">
<term><command>ipcs</command></term>
<listitem>
<indexterm zone="ch-system-util-linux ipcs"><primary sortas="b-ipcs">ipcs</primary></indexterm>
<para>provides IPC status information.</para>
</listitem>
</varlistentry>

<varlistentry id="isosize">
<term><command>isosize</command></term>
<listitem>
<indexterm zone="ch-system-util-linux isosize"><primary sortas="b-isosize">isosize</primary></indexterm>
<para>reports the size of an iso9660 file system.</para>
</listitem>
</varlistentry>

<varlistentry id="line">
<term><command>line</command></term>
<listitem>
<indexterm zone="ch-system-util-linux line"><primary sortas="b-line">line</primary></indexterm>
<para>copies a single line.</para>
</listitem>
</varlistentry>

<varlistentry id="logger">
<term><command>logger</command></term>
<listitem>
<indexterm zone="ch-system-util-linux logger"><primary sortas="b-logger">logger</primary></indexterm>
<para>enters the given message into the system log.</para>
</listitem>
</varlistentry>

<varlistentry id="look">
<term><command>look</command></term>
<listitem>
<indexterm zone="ch-system-util-linux look"><primary sortas="b-look">look</primary></indexterm>
<para>displays lines that begin with the given string.</para>
</listitem>
</varlistentry>

<varlistentry id="losetup">
<term><command>losetup</command></term>
<listitem>
<indexterm zone="ch-system-util-linux losetup"><primary sortas="b-losetup">losetup</primary></indexterm>
<para>is used to set up and control loop devices.</para>
</listitem>
</varlistentry>

<varlistentry id="mcookie">
<term><command>mcookie</command></term>
<listitem>
<indexterm zone="ch-system-util-linux mcookie"><primary sortas="b-mcookie">mcookie</primary></indexterm>
<para>generates magic cookies, 128-bit random hexadecimal numbers, 
for <command>xauth</command>.</para>
</listitem>
</varlistentry>

<varlistentry id="mkfs">
<term><command>mkfs</command></term>
<listitem>
<indexterm zone="ch-system-util-linux mkfs"><primary sortas="b-mkfs">mkfs</primary></indexterm>
<para>is used to build a file system on a device
(usually a hard disk partition).</para>
</listitem>
</varlistentry>

<varlistentry id="mkfs.bfs">
<term><command>mkfs.bfs</command></term>
<listitem>
<indexterm zone="ch-system-util-linux mkfs.bfs"><primary sortas="b-mkfs.bfs">mkfs.bfs</primary></indexterm>
<para>creates an SCO (Santa Cruz Operations) bfs file system.</para>
</listitem>
</varlistentry>

<varlistentry id="mkfs.cramfs">
<term><command>mkfs.cramfs</command></term>
<listitem>
<indexterm zone="ch-system-util-linux mkfs.cramfs"><primary sortas="b-mkfs.cramfs">mkfs.cramfs</primary></indexterm>
<para>creates a cramfs file system.</para>
</listitem>
</varlistentry>

<varlistentry id="mkfs.minix">
<term><command>mkfs.minix</command></term>
<listitem>
<indexterm zone="ch-system-util-linux mkfs.minix"><primary sortas="b-mkfs.minix">mkfs.minix</primary></indexterm>
<para>creates a Minix file system.</para>
</listitem>
</varlistentry>

<varlistentry id="mkswap">
<term><command>mkswap</command></term>
<listitem>
<indexterm zone="ch-system-util-linux mkswap"><primary sortas="b-mkswap">mkswap</primary></indexterm>
<para>initializes the given device or file to be used as a swap area.</para>
</listitem>
</varlistentry>

<varlistentry id="more">
<term><command>more</command></term>
<listitem>
<indexterm zone="ch-system-util-linux more"><primary sortas="b-more">more</primary></indexterm>
<para>is a filter for paging through text one
screen full at a time. But <command>less</command> is much better.</para>
</listitem>
</varlistentry>

<varlistentry id="mount">
<term><command>mount</command></term>
<listitem>
<indexterm zone="ch-system-util-linux mount"><primary sortas="b-mount">mount</primary></indexterm>
<para>attaches the file system on the given device to a specified directory (thus 
hiding the contents of that directory) in the file-system tree.</para>
</listitem>
</varlistentry>

<varlistentry id="namei">
<term><command>namei</command></term>
<listitem>
<indexterm zone="ch-system-util-linux namei"><primary sortas="b-namei">namei</primary></indexterm>
<para>shows the symbolic links in the given pathnames.</para>
</listitem>
</varlistentry>

<varlistentry id="pg">
<term><command>pg</command></term>
<listitem>
<indexterm zone="ch-system-util-linux pg"><primary sortas="b-pg">pg</primary></indexterm>
<para>displays a text file one screen full at a time.</para>
</listitem>
</varlistentry>

<varlistentry id="pivot_root">
<term><command>pivot_root</command></term>
<listitem>
<indexterm zone="ch-system-util-linux pivot_root"><primary sortas="b-pivot_root">pivot_root</primary></indexterm>
<para>makes the given file system the new
root file system of the current process.</para>
</listitem>
</varlistentry>

<varlistentry id="ramsize">
<term><command>ramsize</command></term>
<listitem>
<indexterm zone="ch-system-util-linux ramsize"><primary sortas="b-ramsize">ramsize</primary></indexterm>
<para>is used to set the size of the RAM disk in a bootable image.</para>
</listitem>
</varlistentry>

<varlistentry id="rdev">
<term><command>rdev</command></term>
<listitem>
<indexterm zone="ch-system-util-linux rdev"><primary sortas="b-rdev">rdev</primary></indexterm>
<para>is used to query and set the root
device and other things in a bootable image.</para>
</listitem>
</varlistentry>

<varlistentry id="readprofile">
<term><command>readprofile</command></term>
<listitem>
<indexterm zone="ch-system-util-linux readprofile"><primary sortas="b-readprofile">readprofile</primary></indexterm>
<para>reads kernel profiling information.</para>
</listitem>
</varlistentry>

<varlistentry id="rename">
<term><command>rename</command></term>
<listitem>
<indexterm zone="ch-system-util-linux rename"><primary sortas="b-rename">rename</primary></indexterm>
<para>renames the given files, replacing a given string with another.</para>
</listitem>
</varlistentry>

<varlistentry id="renice">
<term><command>renice</command></term>
<listitem>
<indexterm zone="ch-system-util-linux renice"><primary sortas="b-renice">renice</primary></indexterm>
<para>is used to alter the priority of running processes.</para>
</listitem>
</varlistentry>

<varlistentry id="rev">
<term><command>rev</command></term>
<listitem>
<indexterm zone="ch-system-util-linux rev"><primary sortas="b-rev">rev</primary></indexterm>
<para>reverses the lines of a given file.</para>
</listitem>
</varlistentry>

<varlistentry id="rootflags">
<term><command>rootflags</command></term>
<listitem>
<indexterm zone="ch-system-util-linux rootflags"><primary sortas="b-rootflags">rootflags</primary></indexterm>
<para>is used to set the rootflags in a bootable image.</para>
</listitem>
</varlistentry>

<varlistentry id="script">
<term><command>script</command></term>
<listitem>
<indexterm zone="ch-system-util-linux script"><primary sortas="b-script">script</primary></indexterm>
<para>makes a typescript of a terminal session, of everything printed to 
the terminal.</para>
</listitem>
</varlistentry>

<varlistentry id="setfdprm">
<term><command>setfdprm</command></term>
<listitem>
<indexterm zone="ch-system-util-linux setfdprm"><primary sortas="b-setfdprm">setfdprm</primary></indexterm>
<para>sets user-provided floppy disk parameters.</para>
</listitem>
</varlistentry>

<varlistentry id="setsid">
<term><command>setsid</command></term>
<listitem>
<indexterm zone="ch-system-util-linux setsid"><primary sortas="b-setsid">setsid</primary></indexterm>
<para>runs the given program in a new session.</para>
</listitem>
</varlistentry>

<varlistentry id="setterm">
<term><command>setterm</command></term>
<listitem>
<indexterm zone="ch-system-util-linux setterm"><primary sortas="b-setterm">setterm</primary></indexterm>
<para>is used to set terminal attributes.</para>
</listitem>
</varlistentry>

<varlistentry id="sfdisk">
<term><command>sfdisk</command></term>
<listitem>
<indexterm zone="ch-system-util-linux sfdisk"><primary sortas="b-sfdisk">sfdisk</primary></indexterm>
<para>is a disk partition table manipulator.</para>
</listitem>
</varlistentry>

<varlistentry id="swapdev">
<term><command>swapdev</command></term>
<listitem>
<indexterm zone="ch-system-util-linux swapdev"><primary sortas="b-swapdev">swapdev</primary></indexterm>
<para>is used to set the swap device in a bootable image.</para>
</listitem>
</varlistentry>

<varlistentry id="swapoff">
<term><command>swapoff</command></term>
<listitem>
<indexterm zone="ch-system-util-linux swapoff"><primary sortas="b-swapoff">swapoff</primary></indexterm>
<para>disables devices and files for paging and swapping.</para>
</listitem>
</varlistentry>

<varlistentry id="swapon">
<term><command>swapon</command></term>
<listitem>
<indexterm zone="ch-system-util-linux swapon"><primary sortas="b-swapon">swapon</primary></indexterm>
<para>enables devices and files for paging and swapping.</para>
</listitem>
</varlistentry>

<varlistentry id="tunelp">
<term><command>tunelp</command></term>
<listitem>
<indexterm zone="ch-system-util-linux tunelp"><primary sortas="b-tunelp">tunelp</primary></indexterm>
<para>is used to tune the parameters of the line printer.</para>
</listitem>
</varlistentry>

<varlistentry id="ul">
<term><command>ul</command></term>
<listitem>
<indexterm zone="ch-system-util-linux ul"><primary sortas="b-ul">ul</primary></indexterm>
<para>is a filter for translating underscores into
escape sequences indicating underlining for the terminal in use.</para>
</listitem>
</varlistentry>

<varlistentry id="umount">
<term><command>umount</command></term>
<listitem>
<indexterm zone="ch-system-util-linux umount"><primary sortas="b-umount">umount</primary></indexterm>
<para>disconnects a file system from the system's file tree.</para>
</listitem>
</varlistentry>

<varlistentry id="vidmode">
<term><command>vidmode</command></term>
<listitem>
<indexterm zone="ch-system-util-linux vidmode"><primary sortas="b-vidmode">vidmode</primary></indexterm>
<para>could be used to set the video mode in a bootable image.</para>
</listitem>
</varlistentry>

<varlistentry id="whereis">
<term><command>whereis</command></term>
<listitem>
<indexterm zone="ch-system-util-linux whereis"><primary sortas="b-whereis">whereis</primary></indexterm>
<para>reports the location of binary, the
source, and the manual page for the given command.</para>
</listitem>
</varlistentry>

<varlistentry id="write">
<term><command>write</command></term>
<listitem>
<indexterm zone="ch-system-util-linux write"><primary sortas="b-write">write</primary></indexterm>
<para>sends a message to the given user,
<emphasis>if</emphasis> that user has not disabled such messages.</para>
</listitem>
</varlistentry>
</variablelist>

</sect2>

</sect1>