Programmer's Wiki

A command line interface is a way of controlling a programs with typed instructions. Commands are typed in to perform some process and the results are printed back to the screen. in Shells each command is a seperate program. With applications that have their own CLI the commands can be implemented using functions within the program.

Command Piping[]

This type of interface originated with Unix based operating systems. The idea behind it was each command would be a specialised tool to solve a particular problem. The results of one program could easily be fed into the input of another. In this way a complex problem could be solved by creating a chain of commands.

I/O Redirection[]

The result of a command can also be sent to a file. This makes it easy to review the results later on.

ls > list.txt

This sends the results of an ls command to the list.txt file. If the file does not exist it is created, otherwise the file is overwritten.

See Also[]