Editing FAT filesystem and Linux (section)

=== Installing Linux on FAT {{anchor| on and booting it from FAT volumes using umsdos}} ===
As mentioned, ''{{Not a typo|umsdos}}'' permits installing Linux on, and then bootstrapping and running it from, a FAT format disc volume.  The advantage of this is that it permits the use of Linux on a computer where [[DOS]] is already installed, without requiring that the hard disc be [[partition (computing)|repartitioned]].  Linux is not bootstrapped directly from a [[Volume Boot Record]] in such a scenario.  Instead DOS is first bootstrapped, and [[loadlin]] or {{Not a typo|linld}} is used to then bootstrap Linux from DOS.<ref name="McCune"/>

The convention for such an installation is for the Linux [[root directory]] to be a subdirectory of the root directory of the DOS [[system partition and boot partition|boot volume]], e.g. <code>C:\LINUX</code> .  The various Linux top-level directories are thus, to DOS, directories such as <code>C:\LINUX\ETC</code> (for <code>/etc</code>), <code>C:\LINUX\BIN</code> (for <code>/bin</code>), <code>C:\LINUX\LIB</code> (for <code>/lib</code>), and so forth.  The ''{{Not a typo|umsdos}}'' filesystem driver automatically prepends the <code>C:\LINUX\</code> to all pathnames.  The location of the Linux root directory is supplied to the ''{{Not a typo|umsdos}}'' filesystem driver in the first place via an option to the <code>loadlin</code> command.  So, for example, <code>loadlin</code> would be invoked with a command line such as <code>loadlin c:\linux\boot\vmlinuz rw root=c:\linux</code> .<ref name="McCune"/><ref name="Danesh">{{cite book |title=Making Linux work: essential tips & techniques |series=1001 Tips Series |author-first=Arman |author-last=Danesh |publisher=Cengage Learning |year=2002 |isbn=978-1-884133-78-7 |pages=[https://archive.org/details/makinglinuxworke00dane/page/19 19] |url=https://archive.org/details/makinglinuxworke00dane/page/19 }}</ref>

The installation of Linux into such a directory in the first place simply involves unpacking files from an archive into that directory and its subdirectories.  Such an installation also generally requires the use of a [[swap file]] rather than a [[swap partition]] for Linux, however this is related to the desire not to repartition the hard disc and unrelated to the ''{{Not a typo|umsdos}}'' filesystem driver per se.<ref name="McCune"/>