Many sources of information on Unix, Linux and the Mac OS X command line are available, but we have selected titles and Web sites of particular value to shell programmers. All Web sites and URLs are valid as of the publication of this book, but as is often the case on the Internet, some may not be available by the time you read this.
There is one reference that you cannot do without. This is the built-in documentation for your particular system, which offers detailed descriptions of the syntax and various options for each command.
If a printed version of your system’s documentation isn’t available, you can use the
man command to get information (referred to as the “man pages”) about any specific Unix ...