Short descriptions of some common UNIX and Linux commands
- Note: A full description of a command may be obtained by using the man pages. Type
"man command" at the prompt and hit return.
- cd - Changes the current working directory.
- chsh - Used to change your shell.
- clear - Clears the screen.
- cp - Copies files.
- ctrl-C - Terminates a process.
- ctrl-D - Closes the session.
- diff - Compares text files.
- echo - Writes its arguments to standard out. E.g., to see what is in your path try echo $PATH.
- file - Determines the file type.
- groups - Displays your group membership.
- head - Displays the beginning of files. E.g., head -n100 myfile will give the top 100 lines of myfile.
- kill - Sends a signal to a running process. E.g., kill 9244576 will terminate process id=9244576.
- ls - Lists and generates statistics for files.
- mkdir - Makes a directory.
- more - Displays a file one screenful at a time. Hit the space bar to go to the next screenful.
- mv - Moves files and directories.
- passwd - Changes the password associated with your username.
- pico - A simple text editor.
- ps - Displays current process status.
- pwd - Displays the pathname of the current working directory.
- rm - Removes files or directories.
- tail - Writes a file to standard output, beginning at a specified point. E.g., tail -n100 myfile displays the last
100 lines of myfile.
- top - Display and update information about the top cpu processes. Useful to see how much memory or cpu usage you have
taken.
- vi - A text editor. For editing files with a full screen display.
- wc - Counts the lines, words, characters, and bytes in a file.