The following typographical conventions are used in this book:
Used for filenames and pathnames, hostnames, domain names, commands,
URLs, and email addresses. Italic is also used
for new terms where they are defined.
- Constant width
Used for code examples and fragments.
- Constant width bold
Used for user input.
- Constant width italic
Used to indicate text that is replaceable.
Indicates a tip, suggestion, or general note.
Indicates a warning or caution.
One particularly important convention in this book involves the use
of command line prompts. I can't say it too often:
don't get into the habit of su'ing
to root whenever you have to do anything remotely administrative.
Even worse, don't say
"It's my machine, I can do anything
as root." Use root privileges only when you really
need them. You'll be safer that way;
you'll have some protection against your own
mistakes, and against attacks made by outsiders.
To show you when you need root privileges, commands requiring root
privileges are preceded by the root prompt, #. Commands that
don't require root privileges are preceded by the
default bash shell prompt, $.
Don't be confused—there are many file listings
in the book, and in many of these files, comments are preceded by #.
Yes, it can be confusing, but you'll get used to it.