Linux Command Directory
This directory of Linux commands is from Linux in a Nutshell, 5th Edition.
Click on any of the 687 commands below to get a description and list of available options. All links in the command summaries point to the online version of the book on Safari Bookshelf.
env [option] [variable=value ... ] [command]
Display the current environment or, if an environment variable is specified, set it to a new value and display the modified environment. If command is specified, execute it under the modified environment.
Ignore current environment entirely.
Unset the specified variable.
Print help message and then exit.
Print version information and then exit.