chapter06/ed-inst.xml


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<sect2><title>&nbsp;</title><para>&nbsp;</para></sect2>

<sect2>
<title>Installation of Ed</title>

<note><para>Ed isn't something which many people use. It's installed here
because it can be used by the patch program if you encounter an ed-based patch
file. This happens rarely because diff-based patches are preferred these
days.</para></note>

<para>This package requires its patch to be applied before you can
install it.</para>

<para><screen><userinput>
patch -Np1 -i ../ed-&ed-patch-version;.patch
</userinput></screen></para>

<para>Prepare Ed to be compiled:</para>

<para><screen><userinput>
./configure --prefix=/usr</userinput></screen></para>

<para>Continue with compiling the package:</para>

<para><screen><userinput>make</userinput></screen></para>

<para>And finish off installing the package:</para>

<para><screen><userinput>make install</userinput></screen></para>

<para>Move the Ed binaries to the root partition.</para>

<para><screen><userinput>mv /usr/bin/{ed,red} /bin
</userinput></screen></para>

</sect2>

<sect2>
<title>Command explanations</title>

<para><userinput>patch -Np1 -i ../ed-&ed-version;.patch:</userinput> This
patch fixes a symlink vulnerability in ed. The ed executable creates files
in /tmp with predictable names. By using various symlink attacks, it is
possible to have ed write to files it should not, change the permissions
of files, etc.</para>

<para><userinput>mv /usr/bin/{ed,red} /bin:</userinput>
The Ed binaries are moved to the /bin directory so they may be used in
the event that the /usr partition is unavailable.</para>

</sect2>