The following typographical conventions are used in this book:
Indicates new terms, URLs, email addresses, filenames, file extensions, pathnames, directories, and Unix utilities.
Indicates commands, options, switches, variables, attributes, keys, functions, types, classes, namespaces, methods, modules, properties, parameters, values, objects, events, event handlers, XML tags, macros, the contents of files, and the output from commands.
Constant width bold
Shows commands and other text that should be typed literally by the user, as well as important lines of code.
Constant width italic
Shows text that should be replaced with user-supplied values.
This icon signifies a tip, suggestion, or general note.
This icon indicates a warning or caution.