Ed-0.2

Ed is a line-oriented text editor. It is used to create, display, modify and otherwise manipulate text files, both interactively and via shell scripts. Ed isn't something which many people use. It's described 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.

Ed normally uses the mktemp function to create temporary files in /tmp, but this function contains a vulnerability (see the section on Temporary Files at http://en.tldp.org/HOWTO/Secure-Programs-HOWTO/avoid-race.html). Apply the following patch to make Ed use mkstemp instead, a secure way to create temporary files:

patch -Np1 -i ../ed-0.2-mkstemp-1.patch

Install Ed by running the following commands:

./configure --prefix=/usr --exec-prefix="" &&
make

Now, as the root user:

make install

--exec-prefix="": This forces the programs to be installed into the /bin directory. Having the programs available there is useful in the event of the /usr partition being unavailable.