Ecommerce web host - You can usually tell at a glance the
You can usually tell at a glance the difference between a variable and an envi- ronment variable in bash. The normal convention is to name local variablesin all lowercase or in mixed-case characters. An environment variable, how- ever, is usually always in all uppercase letters. Checking out commonly used environment variablesThe bash shell has many environment variables. You may be amazed at therange of items these variables store. The handy thing is that, if something isstored in a variable, you can change it to suit your needs! In Table 14-1, I listthe environment variables you re most likely to want to work with. Table 14-1Commonly Used bash Environment VariablesEnvironment VariablePurposeValueHISTSIZEDetermines the number Number of of previously typed com-commandsmands that are stored. HOMESets the location of your The path to your home directory.home directoryMAILCHECKSets how often the bashNumber of seconds shell checks for new mail to wait between in your mailbox. If mail has checksarrived, you see a message similar to You have new mailthe next time you do something at the command prompt. PATHSets the directories that Colon-separated bashlooks in, and the order directoriesto look in them to find a pro- gram name you type at the command prompt. PS1Sets your command prompt.Command and for- matting characters used to form the prompt285Chapter 14: Working without the GUI20_