-
Filenames are case sensitive. That is, MYFILE and
MyFile are different files.
-
The root directory is referred to as simply /. Don't confuse this
"root" with the root user. See
Login to a
shell prompt as root, Section 4.1.1.
-
Every directory has a name which can contain any letters or symbols
except /. [
31] The root directory is an exception; its name is
/ (pronounced "slash" or "the root directory")
and it cannot be renamed.
-
Each file or directory is designated by a fully-qualified
filename, absolute filename, or
path, giving the sequence of directories which must be passed
through to reach it. The three terms are synonymous. All absolute filenames
begin with the / directory, and there's a / between
each directory or file in the filename. The first / is the name
of a directory, but the others are simply separators to distinguish the parts
of the filename.
The words used here can be confusing. Take the following example:
/usr/share/keytables/us.map.gz
This is a fully-qualified filename; some people call it a
path. However, people will also refer to
us.map.gz alone as a filename. [
32]
-
The root directory has a number of branches, such as /etc/ and
/usr/. These subdirectories in turn branch into still more
subdirectories, such as /etc/init.d/ and /usr/local/.
The whole thing together is called the directory tree.
You can think of an absolute filename as a route from the base of the tree
(/) to the end of some branch (a file). You'll also hear people
talk about the directory tree as if it were a family tree:
thus subdirectories have parents, and a path shows the
complete ancestry of a file.
There are also relative paths that begin somewhere other than the root
directory. You should remember that the directory ../ refers to
the parent directory.
-
There's no directory that corresponds to a physical device, such as your hard
disk. This differs from CP/M, DOS, and Windows, where all paths begin with a
device name such as C:\. See
The
filesystem concept in Debian, Section 4.5.2.
