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Username: Julia Caceres Villalobos Book: SAMS Teach Yourself Unix in 24 Hours FOURTH EDITION. No part of any chapter or book may be reproduced or
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Workshop
The Workshop summarizes the key terms you learned and poses some questions about the topics presented in this
chapter. It also provides you with a preview of what you will learn in the next hour.
Key Terms
absolute filename Any filename that begins with a leading slash ( /); these always uniquely
describe a single file in the file system.
binary A file format that is intended for the computer to work with directly rather than for humans
to peruse. See also executable.
device driver All peripherals attached to the computer are called devices in Unix, and each has a
control program always associated with it, called a device driver. Examples are the device drivers for
the display, keyboard, mouse, and all hard disks.
directory A type of Unix file used to group other files. Files and directories can be placed inside
other directories, to build a hierarchical system.
directory separator character On a hierarchical file system, there must be some way to specify
which parts of a full filename are directories and which part is the actual filename itself. This
becomes particularly true when you're working with absolute filenames. In Unix, the directory
separator character is the slash ( /), so a filename like /tmp/testme is easily interpreted as a
file called testme in a directory called tmp .
dot A shorthand notation for the current directory.
dot dot A shorthand notation for the directory one level higher up in the hierarchical file system
from the current location.
dot file A configuration file used by one or more programs. These files are called dot files because
the first letter of the filename is a dot, as in .profile or .login . Because they're dot files,
the ls command doesn't list them by default, making them also hidden files in Unix. See also
hidden file.
executable A file that has been set up so that Unix can run it as a program. This is also shorthand
for a binary file. You also sometimes see the phrase binary executable, which is the same thing. See
