A simple Unix shell written in C++.
Written by Will Taylor and James Stewart for our Operating Systems course at Texas Christian University.
- Internal commands:
help
Displays a list of internal commands with their descriptionscd DIRECTORY
Switches the current working directory to DIRECTORY.history
Displays a list of the last 10 executed user commands!!
Executes the most recent command in the history!N
If N is a positive integer, the Nth command in the history queue is executedalarm N
Where N is a positive integer, an alarm is set that will go off in N seconds. Only one alarm may be set at one time. If N=0, then any previously set alarm will be canceled.exit
orquit
Terminates the BlueShell application
- Processes are initiated by forking a child process using the
fork
syscall. - Backgrounding of processes is allowed by placing
&
after the command. - I/O redirection: I/O redirection is implemented with the
dup2
syscalls (cmd0 >> cmd1
) or (cmd0 << cmd1
). - Piping: single piping is allowed by using (
cmd0 | cmd1
). Implemented withdup2
andpipe
syscalls.