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.
Consult /var/run/utmp for user's login name. If found, print it; otherwise, exit with an error message.
Print a help message and then exit.
Print version information and then exit.