Conventions used

There are a number of text conventions used throughout this book.

CodeInText: Indicates code words in text, database table names, folder names, filenames, file extensions, path names, dummy URLs, user input, and Twitter handles. Here is an example: "We can check that using the which command, which will return the absolute path of AWK on our system."

Any command-line input or output is written as follows:

[ shiwang@linux ~ ] $ sudo apt-get update -y
[ shiwang@linux ~ ] $ sudo apt-get install gawk -y

Bold: Indicates a new term, an important word, or words that you see onscreen. For example, words in menus or dialog boxes appear in the text like this. Here is an example: "It was updated and replaced in the mid-1980s with an enhanced version called New AWK (NAWK)."