When run, command prompts are printed, and commands are read in from the user one line at a time and executed. This file first outlines how to run the program, then gives details on how it works, then give the bugs and problems with this programm.
The following is the instructions for running the command shell
$ git clone https://github.com/yourusername/rshell.git
$ cd rshell
$ git checkout hw0
$ make
$ bin/rshell
Running make creates the executable and places it into a created directory bin. Running make clean will delete the directory bin and everything in it.
One the program has be run, commands should be given like so
executable [ argumentList ] [ connector command ]
Where connectors can be ;, &&, or ||. The executable is an executable program in the PATH.
To exit the program, the user types exit at the beginning of a command.
When exit is found, anything following it will not execute.
Any single & or | will be ignored.
Anything following a # is considered a comment, and thus will be ignored.
The directory tests holds a exec.script file with test cases.
For connectors, if a command will not be executed due to the connector before it, all other commands after will also not execute. For example
true || ls && pwd
will only execute the first command (here true), but because it suceeded,
and thus ls won't be executed, then pwd will also not be executed.
- If the user input has only tabs or spaces before a
|or a&at the beginning, before any commands, it causes a segmentation fault and quits the program. examples:
|| ls
& ps
- The program will only hold up to 99 arguments for every command.